# National Ophthalmology Database Audit

Year 2 Annual Report - The First Prospective Report of the National Ophthalmology Database Audit
2017
The Royal College of Ophthalmologists (RCOphth) is the professional body for eye doctors, who are medically qualified and have undergone or are undergoing specialist training in the treatment and management of eye disease, including surgery. As an independent charity, we pride ourselves on providing impartial and clinically based evidence, putting patient care and safety at the heart of everything we do. Ophthalmologists are at the forefront of eye health services because of their extensive training and experience. The Royal College of Ophthalmologists received its Royal Charter in 1988 and has a membership of over 4,000 consultants of all grades. We are not a regulatory body, but we work collaboratively with government, health and charity organisations to recommend and support improvements in the coordination and management of eye care both nationally and regionally.

Healthcare Quality Improvement Partnership (HQIP) is led by a consortium of the Academy of Medical Royal Colleges, the Royal College of Nursing and National Voices. Its aim is to promote quality improvement, and in particular to increase the impact that clinical audit has on healthcare quality in England and Wales. HQIP holds the contract to manage and develop the National Clinical Audit Programme, comprising more than 30 clinical audits that cover care provided to people with a wide range of medical, surgical and mental health conditions. The programme is funded by NHS England, the Welsh Government and, with some individual audits, also funded by the Health Department of the Scottish Government, DHSSPS Northern Ireland and the Channel Islands. 

## Document Authors:

Paul Henry John Donachie John M Sparrow Date: June 2017

## Copyright

All rights reserved. Applications for the copyright owner's written permission to reproduce significant parts of this publication (including photocopying or storing it in any medium by electronic means and whether or not transiently or incidentally to some other use of this publication) should be addressed to the publisher. Brief extracts from this publication may be reproduced without the written permission of the copyright owner, provided that the source is fully acknowledged.

## Copyright © Healthcare Quality Improvement Partnership, 2017 Contents

| 	                                           | 8.7 Operation characteristics	                                               | 27                                          |
|-------------------------------------------|-----------------------------------------------|---------------------------------------------|
| Acknowledgements                          | 4                                             |                                             |
|                                           | 8.8 Operative complications                   | 27                                          |
| The RCOphth NOD Audit Team                | 4                                             |                                             |
|                                           | 8.9 Postoperative complications               | 29                                          |
| Foreword                                  | 5                                             |                                             |
|                                           | 8.10  Postoperative visual acuity             | 30                                          |
| Executive Summary                         | 6                                             |                                             |
|                                           | 8.11 Change in visual acuity                  | 32                                          |
|                                           | Background and aims of the audit              | 6                                           |
|                                           | Results                                       | 7                                           |
|                                           | 8.12 Case complexity adjusted PCR results     | 37                                          |
|                                           | Recommendations                               | 7                                           |
|                                           | 8.13                                          | Case complexity adjusted visual             |
| loss results                              | 42                                            |                                             |
| 1.  Introduction                          | 10                                            |                                             |
| 9. Summary of Key Points                  | 44                                            |                                             |
| 2. Audit Framework                        | 11                                            |                                             |
| 10. Glossary                              | 45                                            |                                             |
| 3. Aims                                   | 11                                            |                                             |
| 11. Graphs and Tables                     | 47                                            |                                             |
| 4.                                        | NHS Trust / Health Board and Surgeon          | 12                                          |
| Participation                             |                                               |                                             |
|                                           | Interpreting the Graphs                       | 47                                          |
| 5. Methodology                            | 12                                            |                                             |
| 12. References                            | 48                                            |                                             |
|                                           | 5.1 Context of the data collection            | 12                                          |
| Appendix 1: Governance Structure          | 49                                            |                                             |
|                                           | 5.2 Limitations of the data                   | 12                                          |
|                                           | 5.3 Case ascertainment                        | 13                                          |
|                                           | 5.4 Data quality and completeness             | 13                                          |
| Appendix 2: National Ophthalmology        | 50                                            |                                             |
| Database Audit Project Steering Group     |                                               |                                             |
| Membership                                |                                               |                                             |
|                                           | 5.5 Small numbers policy                      | 13                                          |
| Appendix 3: Case Definitions              | 51                                            |                                             |
|                                           | 5.6 Outliers policy                           | 13                                          |
|                                           | Eligible Cataract Surgery Criteria            | 51                                          |
| 6.                                        | Data Extraction, Cleaning                     | 14                                          |
| and Statistical Methods                   |                                               |                                             |
|                                           |                                               | PCR - Posterior Capsule Rupture or Vitreous |
| Prolapse or both                          | 51                                            |                                             |
| 7. Definitions                            | 14                                            |                                             |
|                                           | Visual Acuity (VA)                            | 51                                          |
|                                           | 7.1 Dataset                                   | 14                                          |
| Appendix 4: Ocular co-pathology changes   | 53                                            |                                             |
|                                           | 7.2 Surgeon grade                             | 14                                          |
|                                           | 7.3 Posterior Capsule Rupture (PCR)           | 14                                          |
| Appendix 5: Operative procedures combined | 55                                            |                                             |
| with phacoemulsification ± IOL            |                                               |                                             |
|                                           | 7.4 Visual Acuity (VA)                        | 14                                          |
| Appendix 6: Eligible cataract surgical    | 56                                            |                                             |
| centres in England and Wales              |                                               |                                             |
|                                           | 7.5                                           | Mixed effects modelling of PCR              |
| and Visual Acuity Loss                    |                                               |                                             |
| Appendix 7: List of tables                | 61                                            |                                             |
| 8. Results                                | 15                                            |                                             |
| Appendix 8: List of figures               | 62                                            |                                             |
|                                           | 8.1 Cataract procedures reported to the audit | 15                                          |
|                                           | 8.2 Patient characteristics - Age and Gender  | 21                                          |
|                                           | 8.3                                           | First eye, second eye and simultaneous      |
| bilateral surgery                         |                                               |                                             |
|                                           | 8.4 Index of multiple deprivation             | 21                                          |
|                                           | 8.5 Preoperative Visual Acuity (VA)           | 22                                          |
|                                           | 8.6 Ocular co-pathology                       | 25                                          |

## Acknowledgements

The National Ophthalmology Audit is commissioned by the Healthcare Quality Improvement Partnership (HQIP) and is part of the National Clinical Audit and Patient Outcomes Programme (NCAPOP) and the Consultant Outcomes Programme (COP). We would like to acknowledge the support and guidance we have received from the National Audit Steering Committee which includes professional members, ophthalmologists and optometrists, and patient and public representatives with individual lay members as well as patient support groups being represented. We thank the steering committee for reviewing this report. We also acknowledge the support of the hospitals that participated in the first year of the prospective audit and thank our medical and non-medical colleagues for the considerable time and effort devoted to data collection. All participating centres are acknowledged on the NOD audit website www.nodaudit.org.uk

## The Rcophth Nod Audit Team The Rcophth Project Clinical Lead The Rcophth Nod Delivery Unit

Mr Paul Henry John Donachie Medical Statistician Professor John M Sparrow Consultant Ophthalmologist and Honorary Professor of Ophthalmic Health Services Research and Applied Epidemiology Ms Irene M Stratton Senior Medical Statistician

## The Rcophth Project Executive Lead

Professor Peter Scanlon Consultant Ophthalmologist Ms Kathy Evans Chief Executive, Royal College of Ophthalmologists

## The Rcophth Nod Audit Project Office

Ms Beth Barnes Head of Professional Standards Gloucestershire Retinal Research Group Office Above Oakley Ward Cheltenham General Hospital Gloucestershire GL53 7AN
Ms Martina Olaitan RCOphth NOD Audit Project Support Officer T. 03004 22 2852 E. ghn-tr.nod@nhs.net The Royal College of Ophthalmologists 18 Stephenson Way London NW1 2HD T. +44 (0) 20 7935 0702 F. +44 (0) 20 7383 5258 E. noa.project@rcophth.ac.uk It is with deep regret that we note the death of our friend and colleague Robert Johnston, who sadly died in September 2016. Without his inspirational vision, determination and career long commitment to quality improvement in ophthalmology this work would not have been possible.

## Foreword

The content of this report reflects the activity and outcomes of 120,722 cataract operations, representing nearly one third of all those carried out in England and Wales in 2015/2016. This is an impressive achievement and the team, led by Professor John Sparrow, are to be congratulated on this contribution to key data which are essential to the understanding of the real-life benefits, complications and variation in this high volume surgical field. This information is particularly relevant as it adjusts for patient and preoperative surgical risk and is therefore realistic and non-threatening.  
It is extremely reassuring to note that visual outcomes are good and adverse events infrequent. A number of data sources are being used to submit the information and, while 47% of all Trusts have participated, NOD have been unable to audit the quality of cataract surgery in independent providers but this will be addressed in the next round of data collection. Those who have participated will be using the information positively and more Trusts are coming on board next year to add to the collective data which act to improve learning and contribute to patient safety.

It is recognised that further developments could be made to increase the completeness of the dataset and that commissioners and providers should be aware that all NCAPOP audits are a mandated requirement of the NHS Standard Contract. Cataract surgery is the commonest surgical procedure performed in the UK and Worldwide. This rich source of accurate, high quality data is the envy of other health care systems and those involved should be rightly proud of both developing the mechanisms to collect it and finding ways to analyse and share it usefully and widely. 

## Professor Carrie Macewen President, The Royal College Of Ophthalmologists Executive Summary Background And Aims Of The Audit

Cataract surgery remains the most frequently undertaken NHS surgical procedure with approximately 390,000 cataract operations undertaken in England and 16,000 in Wales during 2015-2016. The Health Quality Improvement Partnership (HQIP) has commissioned the National Ophthalmology Database (NOD) Cataract Audit to report on all NHS funded cataract surgery in England and Wales. The quality of delivery of this high volume surgical activity nationally is unknown, previous reports have been based on data from self-selected centres and thus may not provide a comprehensive picture representative of NHS cataract surgery as a whole. Furthermore, there are ongoing reports of restrictions of access to surgery which may compromise certain population groups in relation to locality or deprivation. The current report documents prospectively collected cataract surgery data and reports results for named NHS centres. These include operations performed and recorded by all surgeons of all grades within centres.  Results for named consultant surgeons will be separately published on the NHS Choices website through the Clinical Outcomes Publication (COP) programme. Two primary indicators of surgical quality are audited. These are, firstly, the index surgical intraoperative complication of rupture of the posterior lens capsule or vitreous prolapse or both (PCR), and secondly Visual Acuity (VA) Loss related to surgery. As an adverse operative event PCR is relevant because it results in a significantly higher risk of harm to the eye and may impact recovery of vision. For example, there is an approximately 40 fold higher risk of a retinal detachment occurring following cataract surgery if PCR occurred. Retinal surgery imposes additional risks, morbidity and cost. Since VA Loss from surgery is the opposite of the intended effect, these key primary outcomes together capture relevant safety elements of surgical quality. Here these outcomes are presented as risk adjusted rates for surgical centres, supported by relevant contextual information including surgical volumes, data completeness, access to surgery and deprivation. The benchmark values of 2.0% for PCR and 1.5% for VA Loss (doubling or worse of the visual angle) and the risk indicators for each of these adverse events were derived from earlier data collections. The audit is designed to avoid duplicate data collection through utilization of data which is collected as part of routine clinical practice. The vast majority of data were obtained through extraction from Electronic Medical Record (EMR) systems, with a small number of centres choosing to submit data from their pre-existing audit databases. The audit is intended to quality assure NHS cataract surgical services for patients whose vision is adversely affected by cataract to the point where they seek surgical intervention. This will be achieved through assessing key indicators of cataract surgical quality within the frames of data completeness and access by centre and deprivation. Should performance fall short of what can reasonably be expected by NHS patients this will be highlighted. 

## Results

Included in this first prospective report are operations undertaken between 1st September 2015 and 31st August 2016. Reported operations were performed in 55 English and one Welsh NHS cataract surgical centres.

## 47%

Approximately 47% of the 125 eligible NHS trusts in England and Wales are thus represented. Around 
9% of cataract operations were excluded for a variety of reasons such as being done for indications other than visual improvement, or being combined with other significant intra-ocular surgery. 120,722 eligible cataract operations were available for analysis which approximates to 30% of all NHS funded cataract surgery undertaken in England and Wales during the audit period. Data completeness was excellent (100%) for the PCR outcome as this is a compulsory operative field in the EMRs. Overall, 1.5% of operations were affected by PCR, slightly below the current benchmark of 2.0%. An eligible preoperative distance VA was recorded for 80.5% of eyes and a postoperative VA for 67.4% of eyes, 57.1% of eyes had both a preoperative and a postoperative 

## Recommendations For Patients

- 
Information should be made easily accessible to the general public
	 - 
Patients, carers and those with an interest in cataract surgery are encouraged to access and view data regarding their local services. Information about the quality of cataract surgery can be viewed online on the National Ophthalmology Audit 
Database website (www.
VA measurement. There was significant variation between centres for completeness of VA data, a reflection of variations in current modes of use of the data collection systems and diverse patient pathways. The median preoperative VA was 0.50 LogMAR units (6/19 Snellen Equivalent); the median postoperative VA was 0.10 LogMAR units (6/7.5 Snellen); and the median change in VA was a 0.38 LogMAR gain. A 'good' postoperative VA of 0.30 (=6/12) or better was achieved in 88.6% of eyes overall, 94.8% of eyes with no ocular co-pathology and 81.4% of eyes with a recorded co-pathology. Overall the VA Loss rate was 0.81%, considerably lower than previously reported and hence lower than the existing benchmark. If confirmed by results from wider centre participation the existing benchmark will require adjustment in future audit cycles. Whilst the audit is able to report on encouragingly large numbers of procedures, there remain centres from which data for the current period are not available. Many centres have indicated that they wish to participate in future audit cycles and as the audit becomes further established increasing uptake will provide a more comprehensive picture of the quality of surgery being undertaken on the NHS.

nodaudit.org.uk) and the HQIP website (www.hqip. org.uk). In addition, data 
can be accessed on the 
NHS Choices website (www. nhs.uk/pages/home.aspx), 
Care Quality Commission 
website **(www.cqc.org.uk)** 
and https://data.gov.uk/ 
	 - 
Patients should ensure they discuss and understand the risks and outcomes of any eye surgery with their consultant

## Recommendations For Providers And Surgeons

 	 - 
Monitoring of adverse events in real time is valuable for the early detection of a rising adverse event rate to ensure timely remedial action can be instituted. This will potentially avoid unnecessary harm to patients through avoidable surgical complications
- 
Care providers and surgeons 
should be familiar with their 
performance 
	 - 
An emphasis on continuous quality monitoring will, in 
addition, lessen the risk of 
a centre or surgeon being identified as an outlier in national reports.
	 	 - 
Centres and surgeons are encouraged to view their performance in regard to outcomes and data completeness
- 
Care providers are reminded that all NCAPOP audits are mandated as a requirement of the NHS Standard Contract and a timely response to the audit providers and their sub-contractors is expected in regard to arrangements for participation in the audit. 
	 	 - 
Where opportunities for quality improvements are found these should be acted upon to enhance the quality of the patient care being provided
	 - 
Care providers are encouraged to adhere to the requirements of the NHS 
standard contract through 
participation in the national audit 
	 	 - 
Care providers should be open and transparent 
regarding their audit 
participation and outcomes and provide relevant information to their patients and the populations they serve
- 
Surgeons and centres are encouraged to ensure accurate and complete data collection for each operation
- 
Care providers and surgeons are encouraged to maximise quality improvement opportunities through making best use of the audit tools that allow real time tracking of adverse event rates locally
	 - 
Risk adjustment can only be successfully applied if the risk indicator data are recorded in the audit data collection tool
	 - 
With these data, surgeons and centres can be given appropriate credit for the complexity of their case mix using the risk adjustment models
	 - 
Without relevant risk adjustment information, operations are assumed to be low risk and, if this is not the case, the reported risk adjusted adverse event 
rate will be higher than the 
unadjusted rate 
- 
Care providers and surgeons should review their patient pathways to maximise the recording of both pre- and postoperative VA data 
	 - 
Care providers are encouraged to implement pathways which collect these data items for every operation

## Recommendations For Commissioners

	 - 
Where outcomes, data completeness or participation are not satisfactory providers should be asked to provide explanations together with their plans for improvements
- 
Commissioners should be familiar with the quality of services which they are 
commissioning on behalf of 
the populations they serve.
- 
Commissioners should ensure all existing or new contracts with NHS funded providers including independent sector treatment centres include 
quality assurance for the wellbeing of the population they serve, through participation in the national audit
	 - 
Commissioners are encouraged to incentivise in quality assurance through participation in the national audit via provider contracts
	 - 
Commissioners are encouraged to view the performance of all providers of the care which they purchase in regard to outcomes and data completeness

## Recommendations For The Regulator

- 
When inspecting NHS organisations, national audit commissioning, participation and performance should be routinely requested from 
commissioners and providers 
of cataract care
	 - 
Regulators should expect participation in national audits with audit results made available to them when inspecting NHS organisations
- 
Commissioners are in a key position to influence VA data returns through appropriate contracting and surgical providers should engage with commissioners and local optometrists to develop such 'enhanced community services'.
	 - 
Commissioners are encouraged to commission services which reward quality 
assurance in regard to visual 
acuity outcome
	 - 
All providers of care should be expected to be in a position to provide quality assurance regardless of whether they are traditional NHS centres or independent providers

## 1. Introduction

In the 2015-2016 year, around 390,000 NHS cataract surgery procedures were undertaken in England and 16,000 in Wales, this being the most frequently performed surgical procedure in the UK. A widely accepted indicator of surgical quality is the frequency of rupture of the posterior capsule or the lens zonules with or without vitreous prolapse into the anterior chamber of the eye, abbreviated as PCR. This surgical event is emphasised in the NICE draft Cataract Surgery Guideline in the context of surgical risk and is similarly used as a clinical outcome (adverse event) by the International Consortium for Health Outcome Measurement **www.ichom.org/medical-conditions/cataracts/**. This operative complication arises on average in approximately one operation in 50 but the risk of this event varies by as much as 50-fold depending on preoperative risk factors associated with the patient and their eye. PCR is relevant as an adverse operative event because it results in a significantly higher risk of harm to the eye and may impact recovery of vision. For example, there is an approximately 40 fold higher risk of a retinal detachment occurring following cataract surgery if PCR occurred, and retinal surgery imposes additional risks, morbidity and cost. Importantly, when PCR occurs there is a six-fold higher chance of loss of vision from pre- to postoperatively in the eye undergoing surgery. Some weeks following cataract surgery most patients attend their community optometrist (high-street optician) for updating of their glasses prescription and then only is the final 'best-corrected' visual acuity established. The results of this follow-up episode are currently inconsistently communicated back to the hospital to allow a definitive measure of visual acuity benefit from surgery. A web-based data return tool has been developed and offered as a free EMR software enhancement to centres to encourage and facilitate these data returns. Since VA Loss from surgery is the opposite of the intended effect, these key primary outcomes together capture relevant safety elements of surgical quality. VA Loss is emphasised in the NICE draft Cataract Surgery Guideline in the context of surgical risk. Providing risk adjusted results for centres and surgeons will facilitate their ability to benchmark their own performance against that of their peers and act as a prompt to reviewing practice where outcomes are less good. Our past experience has indicated that showing individual surgeons their performance stimulates them to be more mindful of quality generally and to improve performance where needed. 

Since safety is a key domain for the NHS, embodied in the oft quoted phrase "do no harm", the audit is primarily focussed on these two chosen safety metrics. The audit tools we provide allow real time tracking of outcomes which empowers centres and surgeons to monitor their results and to detect adverse signals early with a view to minimising patient harm through prompt action. The contextual information presented provides centres and surgeons with secondary process outcomes in terms of access by centre, by deprivation and data completeness. In this first prospective report of the National Ophthalmology Database Audit we will report the case complexity adjusted rates of PCR and monocular visual acuity (VA) loss for named centres (including all surgeons). On the RCOphth NOD website will be posted case complexity adjusted rates of PCR and VA Loss for participating centres and surgeons, and on the NHS choices website will be outcomes for named consultant surgeons for both PCR and VA Loss. Incomplete data will be highlighted and where <40% of outcome data are available for a particular centre (e.g. for VA Loss) the rate will not be reported as deemed too unreliable. Increasing participation is anticipated as the audit develops further and the data collection tools are 'rolled out' to all currently paper-based cataract surgical centres in England and Wales. Five sources of data have been included in the prospective first year of the national cataract audit, 52 centres used the Medisoft EMR, one very large London eye hospital used the OpenEyes EMR and three centres used in-house data collection systems. The data for analysis were extracted in September/October 
2016, with a further extraction of data from the Medisoft EMR and one in-house data collection system in January/February 2017 to address issues encountered in the Autumn 2016 data extractions. Case complexity adjustment for the reported period used risk adjustment models based on 287,000 cataract operations from 34 centres over a four-year time frame up to March 2015. Centres joining the audit towards the end of the data collection period would be expected to have reduced volumes of data. The date for the first submitted operation is included in the results to clarify which centres submitted data for less than the full one year period.

## 2. Audit Framework

The national cataract audit data in this report covers all adult phacoemulsification cataract surgical operations recorded on either the Medisoft EMR at 52 contributing centres, the OpenEyes EMR in use at Moorfields eye hospital (and a number of its satellite units) or in-house cataract data collection systems used in three of the contributing centres. For the PCR outcome the audit included all reported cataract operations performed in the period between 1st September 2015 and 31st August 2016. For the risk adjusted VA Loss outcome and postoperative complications and visual acuity results the reported period was between 1st September 2015 and 30th June 2016 in order to allow time for postoperative data to become available following recovery from surgery. Excluded were cataract operations which were not done by phacoemulsification, operations which were done as combined procedures along with another significant intra-ocular procedure (e.g. a trabeculectomy or a pars plana vitrectomy combined with other vitreoretinal procedures) and operations on individuals aged <18 years. Data on privately funded cataract surgery undertaken by participating surgeons in private hospitals were unavailable and are therefore not included in this report (see Appendix 3 for further details). Centres are identified by name. 

## 3. Aims

The specific aims will be to report risk adjusted rates for two primary patient safety outcomes, PCR and VA Loss in cataract surgery. In this report prospectively collected data are used and applied to risk adjusted models developed from a four-year period of historical data from 34 centres. It is expected that data on PCR will have high levels of completeness for all participating centres as recording of the presence or absence of specified operative complications has always been mandatory in ophthalmology EMR systems but the preoperative risk indicator and follow up VA data are expected to be less complete. The quality improvement aims of this report include

- 
Reporting of the intra-operative complication rates (risk adjusted), thus drawing attention to the need for careful risk profiling of cases in advance of surgery in order to minimise avoidable surgical complications
- 
Reporting the rates of VA Loss, thus drawing attention to potentially avoidable visual harm where rates are elevated
There will be a number of secondary aims developed throughout the life of the audit, in this annual report for example the contextual information includes access (preoperative VA) by centre and by deprivation. 

## 4. Nhs Trust / Health Board And Surgeon Participation

The audit brief is to include all NHS funded cataract surgery in England and Wales where Caldicott Guardians and Clinical Leads have given permission for extraction of their data. As part of the prospective audit the cataract module of an EMR has being made available to all currently paper-based, non-EMR enabled centres. In this report the majority of centres were in England with a single centre in Wales. This report includes currently EMR enabled centres and three centres using an in-house data collection system. Also available is a spreadsheet data entry option which has not to date been used to submit data (which would be inefficient as it would require duplicate data entry).

## 5. Methodology 5.1 Context Of The Data Collection

The audit data derive from routine data collection in NHS hospital trust ophthalmology departments. Complications data depend on surgeons recording these faithfully, unlike mortality figures there is no external validation of the reported complications, although certain cross checks are possible within the extracted data. The EMR requires the surgeon recording the operation note to specifically indicate a Yes/No response to whether a surgical complication occurred and at all centres the EMR record (or its printed copy for the paper notes) constitutes the medicolegal document of the patient's operation record. Accurate follow up data on VA and refraction often depend on patients attending their optometrist for updating of spectacles following surgery and for this information to then be returned to the hospital electronic data collection system. Although some centres have good paper-based systems in place for optometrists to return this information and for staff at the hospital to enter the data electronically, it is anticipated that this outcome will be incomplete and the audit team have therefore taken steps to enhance returns from optometrists through encouraging proactive local engagement with community optometrists, an active programme of engagement with national optometric professional bodies, and provision of a web based data return tool for the National Ophthalmology Audit.

## 5.2 Limitations Of The Data

The RCOphth NOD includes data for cataract operations to the first treated eye, the second treated eye and in some cases simultaneous bilateral surgery, but for some patients the record for the first treated eye may be missing. This may arise for example if the first eye operation was performed prior to the centre adopting an electronic data collection system, or the first treated eye operation could have been performed in a different centre. At present the RCOphth NOD cannot link patients' data if collected at different centres; this will be possible if a section 251 exemption is granted, an information governance permission which would allow patient identifiable data to be used for purposes of linkage between care providers. Patient's age, and calculation of index of multiple deprivation (IMD) data10 rely on data entered directly onto the Hospital's Patient Administration System (PAS) which links into EMR systems, hence if this data is not recorded in the PAS it is not present in the data extract for EMR enabled centres with PAS connections. Centres opting for an EMR installation without a PAS connection would need to record this information along with the other audit data. IMD data was present for many operations recorded on the Medisoft EMR system, but not calculable for the other sources of data as the complete patient postcode would be needed to calculate the IMD data and The RCOphth NOD does not currently have permission to receive this. For future cycles of the national cataract audit the OpenEyes EMR will include IMD data calculated during extraction and transferred to the RCOphth NOD audit.

## 5.3 Case Ascertainment

Exact estimation of the number of cataract operations submitted to the audit as a proportion of the number of cataract operations performed in each participating centre is not possible because:

1.	 
Not all participating centres were collecting their cataract operations in an electronic format for the whole audit period.
2.	 
The national cataract audit has exclusion criteria that would not be in place in other reported sources of the number of cataract operations performed in any centre i.e. surgery combined with another procedure.
Given the above limitations, estimates of the proportion of cataract operations performed in each participating centre that are included in the audit analysis are provided in Table 1. For centres joining the audit during the audit period, the NHS Digital data for the full audit period was adjusted by the proportion of time a centre had recorded data to provide a pro-rata estimate of the number of operations a centre could have recorded. From this adjusted number an estimate of case-ascertainment was calculated where the range in the percentage of eligible cases submitted to the audit was 7.7% to 99.9% and for 33 centres this estimate was >80%.

## 5.4 Data Quality And Completeness

Among the advantages of EMR data collection are compulsory collection of key data items (e.g. operative complications) and automatic range checking of variables (e.g. axial length) at the time of data entry improving data completeness and accuracy. In addition, the richness of EMR data provides a more complete picture of the patient and their state of health making it possible to infer important information through cross checking. (e.g. An undetected breach of the capsule may have occurred at the time of surgery which later became apparent at an outpatient visit. If vitreous was detected in the anterior chamber at the outpatient visit then it can be inferred that a complication must have occurred at the time of surgery and the operation can accordingly be correctly classified). Completeness of preoperative VA and postoperative VA outcome remain variable and an area for improvement in many centres. The Audit tools include a web based data return tool for use by community optometrists which is intended to facilitate return of postoperative data. This works best when optometrists are commissioned to undertake postoperative follow up in the community as contracting can make payment contingent upon data having been received by the surgical centre.

## 5.5 Small Numbers Policy

Centres with <50 operations have not been included in this report and the COP report for individual surgeon results will likewise not report results for surgeons who have undertaken <50 procedures. (This is done for statistical reasons as the estimates would be unreliable and meaningless.) Issues related to reporting on small numbers are therefore not relevant to this audit. 

## 5.6 Outliers Policy

The audit outliers' policy has been developed directly from the HQIP outliers' policy and is available on the NOD Audit website at **www.nodaudit.org.uk/resources/policies**. An outlying centre or surgeon is identified where the risk adjusted adverse event rate (i.e. case complexity taken into account) is above the national threshold set by the mean rate plus three Standard Deviations (3SD). The method takes into account statistical uncertainty related to sample size and there is a one in 1,000 chance that a surgeon or centre would fall above this threshold purely due to 'bad luck'. Where initial analysis suggests a potential outlier may have been identified the centre or surgeon or both are notified and invited to check the accuracy and completeness of the data which has been received by the audit. Where corrections are relevant these are made prior to any results being released into the public domain.

## 6. Data Extraction, Cleaning And Statistical Methods

There are five sources of data included in the prospective first year of the national cataract audit, where 
52 centres used the Medisoft EMR (Medisoft Ophthalmology, Medisoft Limited, Leeds, UK, (www. medisoft.co.uk/), one very large London eye hospital (and a number of its satellites) used the OpenEyes EMR **(www.openeyes.org.uk/)** and three centres used in-house data collection systems. The audit data extractions were performed in September/October 2016, with a further extraction in January/February 2017 of data from the Medisoft EMR and one in-house data collection system to address problems encountered in the Autumn 2016 data extractions. Late in the analysis it was discovered that data for one trust had become corrupted during the extraction period and these data were excluded from reporting. All analysis was conducted using STATA version 14, (StataCorp. 2015. Stata Statistical Software: Release 14. College Station, TX: StataCorp LP). Centre participation was affirmed by agreement from the Trust Caldicott Guardian and Clinical Lead for Ophthalmology.

Full details regarding eligibility and analysis criteria can be found on the NOD audit website following registration www.nodaudit.org.uk

## 7. Definitions 7.1 Dataset

A minimum cataract dataset has been defined for purposes of the audit **www.nodaudit.org.uk**. These variables include those required for case complexity adjustment of outcomes.

## 7.2 Surgeon Grade

The grade of surgeon was categorised as consultant surgeons, career grade non-consultant surgeons (associate specialists, staff grade and trust doctors), experienced trainee surgeons (fellows, registrars, speciality registrars years 3 - 7 and specialty trainees years 3 - 7) and less experienced trainee surgeons (SHO, specialty registrars years 1 - 2, specialty trainees years 1 - 2 and foundation doctors years 1 - 2).

## 7.3 Posterior Capsular Rupture (Pcr)

PCR included posterior capsule rupture or vitreous prolapse or both and was intended to capture significant breach of the lens-zonule barrier. Detailed criteria for case definitions are in Appendix 3.

## 7.4 Visual Acuity (Va)

VA definitions used were designed to maximise the usefulness of the available data with specified 'time windows' for pre- and postoperative measurements and criteria for preferred choices in terms of corrected VA, unaided VA and pin hole corrected VA. The detailed criteria are given in Appendix 3 along with interpretations for levels of VA.

## 7.5 Mixed Effects Modelling Of Pcr And Visual Loss

The categorisation of each covariate under investigation in the PCR and VA Loss mixed effects logistic regression models are detailed for registered users on The RCOphth NOD Audit website  
www.nodaudit.org.uk, with operations performed in the four-year period 2011-12 to 2014-15 NHS years used to develop the current models.

The risk adjustment model equations for PCR and Visual Acuity Loss respectively were applied to the audit data for the respective results in this report where the case mix adjusted graphs have 99.8% error lines displayed which are created from benchmark means of 2.0% for PCR and 1.5% for Visual Acuity Loss. The audit stipulates that at least 40% of operations with both pre- and postoperative VA data are required in order to report a result for VA Loss. On the centre level case mix adjusted funnel plots, data for all surgeons is included (i.e. including trainee surgeons).

## 8. Results 8.1 Cataract Procedures Reported To The Audit

In total 132,678 operations were submitted during the audit period (01 September 2015 to 31 August 2016), of these 11,956 (9.0%) operations are excluded from analysis; the reasons for exclusion were as follows:

- 183 operations were performed on patients <18 years old. - 1,189 operations had no record of phacoemulsification ±IOL. - 6,667 operations had a non-cataract indication for surgery. - 3,878 operations included ineligible combined operative procedures. - Six operations were performed under general anaesthesia and also had examination under 
anaesthetic recorded.
- One operation had an operative note stating "Cataract surgery previously" - 32 operations from four centres were excluded as these centres were recent joiners and had 
submitted <50 eligible operations (two further centres joined just after the audit time window had closed, therefore of the 62 centres from which data were extracted six centres were excluded).
This left 120,722 operations performed in 56 participating centres eligible for analysis. The operations were performed on 59,471 (49.3%) left eyes and 61,251 (50.7%) right eyes from 97,908 patients. These operations were performed by 1,391 surgeons where 85 surgeons had performed surgery at more than one grade. Whilst these are encouragingly large numbers of procedures, there remain many centres from which data for the current period are not available. As the audit becomes further established increasing uptake will provide a more comprehensive picture of the quality of surgery being undertaken on the NHS. The number of surgeons and operations at each surgeon grade were:

- 660 consultant surgeons performed 74,228 (61.5%) operations. - 167 career grade non-consultant surgeons performed 13,219 (10.9%) operations. - 540 experienced trainee surgeons performed 28,927 (24.0%) operations. - 109 less experienced trainee surgeons performed 4,348 (3.6%) operations.
The percentage of operations performed by each grade of surgeon within each centre varied reflecting catchment area, NHS trust differences and training opportunities for junior surgeons within England and Wales, Table 1 and Figure 1. The median number of operations each surgeon had performed was 50 operations (range; 1 - 805), and 696 (49.6%) surgeons had performed >50 operations within the time window, Figure 2. Of the 1,391 surgeons, 914 (65.7%) surgeons were male, 447 (32.1
%) surgeons were female and the surgeon's gender was unknown for 30 (2.2%) surgeon's. 124 (8.8%) surgeons had data for operations performed in 2 participating centres, and 3 (0.4%) surgeons had data for operations performed in 3 participating centres.

Number 
of eligible 
operations
Centre name
Centre 
number
Date of first 
cataract 
operation 
during the 
audit period
Estimate 
of cases 
submitted 
to the audit 
(%)*
1
01/09/2015
10,626
55.7
169
43.5
3.6
52.8
0.0
Moorfields Eye Hospital NHS Foundation Trust (Open Eyes Centre)
2
07/09/2015
7,560
96.7
62
68.1
9.5
19.4
3.0
The Newcastle upon Tyne Hospitals NHS Foundation Trust
3
01/09/2015
4,639
96.9
31
63.7
19.1
12.7
4.5
Norfolk and Norwich University Hospitals NHS Foundation Trust Leeds Teaching Hospitals NHS Trust
4
01/09/2015
4,371
94.8
45
56.5
2.8
32.5
8.1
5
01/09/2015
4,212
89.0
29
82.0
0.0
14.7
3.3
York Teaching Hospital NHS Foundation Trust (In-house database)
6
01/09/2015
4,182
97.4
44
13.5
28.2
58.1
0.2
Oxford University Hospitals NHS Foundation Trust
7
01/09/2015
4,154
96.2
49
54.4
0.0
45.6
0.0
University Hospitals 
Bristol NHS Foundation Trust
8
01/09/2015
4,085
98.9
37
51.0
24.3
21.8
2.9
Gloucestershire Hospitals NHS Foundation Trust
9
01/09/2015
3,829
76.9
37
78.4
3.0
10.3
8.3
Sheffield Teaching Hospitals NHS Foundation Trust
10
01/09/2015
3,332
81.1
80
51.7
9.6
31.9
6.8
Sandwell and West Birmingham Hospitals NHS Trust
11
01/09/2015
3,128
All
47
63.8
0.1
34.0
2.1
University Hospital Southampton NHS Foundation Trust Royal Berkshire NHS Foundation Trust
12
01/09/2015
3,109
59.8
31
57.5
1.9
35.8
4.9

*The estimate of the proportion of cases submitted to the audit is derived from the number of completed cataract operations supplied to NHS digital for the audit period. This estimation uses a pro-rata calculation for a centre's denominator where the proportion of time during the audit cycle that a centre had been recording cataract operations was multiplied by the number of cataract operations supplied to NHS digital. The numerator was the number of eligible operations a centre had in the audit analysis. Centre's that had more operations submitted to the national audit than in the NHS digital data were all assumed to have a complete submission rate (All) as the actual rate was not possible to estimate. **3 centres had no data in the NHS digital data.

The percentage of operations performed by
Number 
of 
surgeons
Experienced 
trainee 
surgeons
Consultant 
surgeons
Career 
grade nonconsultant 
surgeons
Less 
experienced 
trainee 
surgeons
Number 
of eligible 
operations
Centre name
Centre 
number
Date of first 
cataract 
operation 
during the 
audit period
Estimate 
of cases 
submitted 
to the audit 
(%)*
13
01/09/2015
2,864
97.9
26
88.9
7.3
3.9
0.0
Calderdale and Huddersfield NHS Foundation Trust Mid Cheshire Hospitals NHS Foundation Trust
14
01/09/2015
2,637
97.2
22
47.1
34.8
13.7
4.5
The Mid Yorkshire Hospitals NHS Trust
15
02/09/2015
2,615
98.5
17
78.5
15.4
0.0
6.0
Cardiff & Vale University LHB
16
01/09/2015
2,414
NPE**
41
64.9
1.3
33.8
0.0
17
01/09/2015
2,406
100.0
22
76.5
0.0
14.2
9.3
Epsom and St Helier University Hospitals NHS Trust
Barts Health NHS Trust
18
01/09/2015
2,376
85.7
44
43.5
11.5
38.3
6.6
Frimley Health NHS Foundation Trust
19
01/09/2015
2,290
88.1
28
41.5
36.8
10.8
10.9
20
01/09/2015
2,268
96.4
34
78.0
0.0
19.0
3.0
Bradford Teaching Hospitals NHS Foundation Trust
21
01/09/2015
2,257
All
15
76.8
18.7
4.5
0.0
Moorfields Eye Centre at Bedford Hospital NHS Trust Plymouth Hospitals NHS Trust
22
02/09/2015
2,223
82.3
24
39.8
31.6
26.9
1.7
23
01/09/2015
1,977
98.7
39
57.5
0.0
41.1
1.5
University Hospitals Birmingham NHS Foundation Trust
Hampshire Hospitals NHS Foundation Trust
24
01/09/2015
1,975
60.3
17
89.4
1.6
8.1
1.0
Royal Cornwall 
Hospitals NHS Trust
25
01/09/2015
1,969
96.0
20
68.9
22.9
6.9
1.3
26
01/09/2015
1,952
46.0
46
48.3
9.4
39.7
2.7
Central Manchester University Hospitals NHS Foundation Trust
King's College Hospital NHS Foundation Trust
27
01/09/2015
1,924
30.0
45
59.1
0.5
37.0
3.4
28
01/09/2015
1,920
100.0
22
85.3
6.0
3.3
5.4
Shrewsbury and Telford Hospital NHS Trust
29
04/09/2015
1,824
NPE**
26
37.3
37.1
22.2
3.4
Moorfields Eye Centre at Croydon Health Services NHS Trust
30
01/09/2015
1,693
99.2
23
36.9
6.6
49.5
7.0
The Hillingdon Hospitals NHS Foundation Trust

*The estimate of the proportion of cases submitted to the audit is derived from the number of completed cataract operations supplied to NHS digital for the audit period. This estimation uses a pro-rata calculation for a centre's denominator where the proportion of time during the audit cycle that a centre had been recording cataract operations was multiplied by the number of cataract operations supplied to NHS digital. The numerator was the number of eligible operations a centre had in the audit analysis. Centre's that had more operations submitted to the national audit than in the NHS digital data were all assumed to have a complete submission rate (All) as the actual rate was not possible to estimate. **3 centres had no data in the NHS digital data.

The percentage of operations performed by
Number 
of 
surgeons
Experienced 
trainee 
surgeons
Consultant 
surgeons
Career 
grade nonconsultant 
surgeons
Less 
experienced 
trainee 
surgeons
Number 
of eligible 
operations
Centre name
Centre 
number
Date of first 
cataract 
operation 
during the 
audit period
Estimate 
of cases 
submitted 
to the audit 
(%)*
31
01/09/2015
1,626
93.9
29
57.8
10.8
27.5
3.9
Aintree University Hospital NHS Foundation Trust
32
01/09/2015
1,597
94.5
16
66.8
3.7
14.7
14.8
Royal United Hospitals Bath NHS Foundation Trust
33
01/09/2015
1,472
98.6
13
100.0
0.0
0.0
0.0
Chesterfield Royal Hospital NHS Foundation Trust
Mid Essex Hospital Services NHS Trust
34
01/09/2015
1,462
93.5
16
76.9
7.9
13.4
1.7
Harrogate and District NHS Foundation Trust
35
02/09/2015
1,461
99.8
11
66.7
16.4
6.2
10.7
Hinchingbrooke Health Care NHS Trust
36
01/09/2015
1,458
98.1
9
87.2
0.0
12.8
0.0
Northern Devon Healthcare NHS Trust
37
01/09/2015
1,431
99.6
13
49.9
23.4
26.7
0.0
38
02/09/2015
1,402
99.6
14
65.9
21.7
6.5
5.9
Peterborough and Stamford Hospitals NHS Foundation Trust
39
01/09/2015
1,351
94.7
20
75.4
0.0
20.7
4.0
Wirral University Teaching Hospital NHS Foundation Trust
South Warwickshire NHS Foundation Trust
40
01/09/2015
1,286
99.0
8
71.7
28.3
0.0
0.0
Isle of Wight NHS Trust
41
01/09/2015
1,222
94.9
10
66.9
24.5
8.6
0.0
42
01/09/2015
1,135
61.9
13
83.9
11.0
5.1
0.0
St Helens and Knowsley Teaching Hospitals NHS Trust
43
29/10/2015
993
64.3
7
85.8
14.2
0.0
0.0
Wrightington, Wigan 
and Leigh NHS Foundation Trust
44
29/01/2016
855
64.0
14
75.2
1.4
3.9
19.5
Warrington and Halton Hospitals NHS Foundation Trust
South Tees Hospitals NHS Foundation Trust
45
18/09/2015
687
25.1
22
81.1
7.1
11.8
0.0
46
08/03/2016
574
32.7
15
75.8
24.2
0.0
0.0
The Royal Bournemouth and Christchurch Hospitals NHS Foundation Trust
47
03/09/2015
568
36.8
14
78.9
9.3
3.2
8.6
Barking, Havering and Redbridge University Hospitals NHS Trust
Royal Free London NHS Foundation Trust
48
09/02/2016
552
17.3
28
52.7
7.8
19.6
19.9

*The estimate of the proportion of cases submitted to the audit is derived from the number of completed cataract operations supplied to NHS digital for the audit period. This estimation uses a pro-rata calculation for a centre's denominator where the proportion of time during the audit cycle that a centre had been recording cataract operations was multiplied by the number of cataract operations supplied to NHS digital. The numerator was the number of eligible operations a centre had in the audit analysis. Centre's that had more operations submitted to the national audit than in the NHS digital data were all assumed to have a complete submission rate (All) as the actual rate was not possible to estimate. **3 centres had no data in the NHS digital data.

The percentage of operations performed by
Number 
of 
surgeons
Experienced 
trainee 
surgeons
Consultant 
surgeons
Career 
grade nonconsultant 
surgeons
Less 
experienced 
trainee 
surgeons
Number 
of eligible 
operations
Centre name
Centre 
number
Date of first 
cataract 
operation 
during the 
audit period
Estimate 
of cases 
submitted 
to the audit 
(%)*
49
09/11/2015
551
25.4
22
43.9
42.5
4.7
8.9
University Hospitals Coventry and Warwickshire NHS Trust
50
24/03/2016
458
NPE**
5
76.9
23.1
0.0
0.0
Barnsley Hospital NHS Foundation Trust (Inhouse database) Salisbury NHS Foundation Trust
51
13/01/2016
453
47.4
9
87.0
3.3
7.3
2.4
52
02/09/2015
325
44.8
14
36.3
35.4
28.3
0.0
London North West Healthcare NHS Trust (In-house database)
53
01/09/2015
297
11.3
12
54.5
32.7
0.0
12.8
Blackpool Teaching Hospitals NHS Foundation Trust
54
19/10/2015
288
11.1
7
88.9
11.1
0.0
0.0
University Hospitals of Morecambe Bay NHS Foundation Trust
55
02/09/2015
250
7.7
14
62.0
0.0
38.0
0.0
Nottingham University Hospitals NHS Trust
Yeovil District Hospital NHS Foundation Trust
56
18/04/2016
157
54.7
2
100.0
0.0
0.0
0.0

*The estimate of the proportion of cases submitted to the audit is derived from the number of completed cataract operations supplied to NHS digital for the audit period. This estimation uses a pro-rata calculation for a centre's denominator where the proportion of time during the audit cycle that a centre had been recording cataract operations was multiplied by the number of cataract operations supplied to NHS digital. The numerator was the number of eligible operations a centre had in the audit analysis. Centre's that had more operations submitted to the national audit than in the NHS digital data were all assumed to have a complete submission rate (All) as the actual rate was not possible to estimate. **3 centres had no data in the NHS digital data.

The percentage of operations performed by
Number 
of 
surgeons
Experienced 
trainee 
surgeons
Consultant 
surgeons
Career 
grade nonconsultant 
surgeons
Less 
experienced 
trainee 
surgeons

## 8.2 Patient Characteristics - Age And Gender

Summary details of the 97,908 patients undergoing cataract surgery in the first year of the prospective audit were as follows:

- 97,908 patients with median age 76.6 years - 41,830 (42.7%) patients were men with median age 76.1 years. - 55,895 (57.1%) patients were women with median age 77.0 years. - The gender was not recorded for 183 (0.2%) patients with median age 77.0 years. - The ethnicity was not recorded for 45,158 (46.1%) patients.

## 8.3 First Eye, Second Eye And Simultaneous Bilateral Surgery

All cataract operations performed during the audit cycle would be in either the patient's first or second treated eye unless simultaneous bilateral surgery was performed. The RCOphth NOD Audit may not have the record for both operations or the first treated eye could have had the operation at another centre or prior to electronic data collection within the centre. For these reasons, no results on time between operations are provided in this report. Results for first and second treated eye operations are reported for the 120,428 operations performed that were not simultaneous bilateral operations.

## First Treated Eye Cataract Surgery;

- First eye cataract surgery was performed for 71,970 (59.8%) operations. - The median age at first treated eye surgery was 76.1 years (range; 18.1 - 114.9). - 19,935 (27.7%) patients were recorded as having diabetes mellitus at the time of 
their first cataract operation.
- 935 (1.3%) patients were recorded to be unable to lie flat. - 833 (1.2%) patients were recorded to be unable to cooperate during the 
operation.

## Second Treated Eye Cataract Surgery;

- Second eye cataract surgery was performed for 48,458 (40.2%) operations. - The median age at second treated eye surgery was 77.2 years (range; 18.3 - 
103.7).
- 13,968 (28.8%) patients were recorded as having diabetes mellitus at the time of 
their second treated eye surgery.
- 494 (1.0%) patients were recorded as being unable to lie flat. - 431 (0.9%) patients were recorded as being unable to cooperate during the 
operation.

## 8.4 Index Of Multiple Deprivation

The index of multiple deprivation (IMD) was calculated for 82,477 (96.7%) patients with cataract surgery data recorded on the Medisoft EMR. All bar four centres performed cataract surgery on patients in the least deprived national decile of social deprivation (decile 1) and all bar two centres performed cataract surgery on patients in the most deprived national decile of social deprivation (decile 10). The median national decile of social deprivation for patients undergoing cataract surgery varied significantly between centres, confirming that there was variation between the participating centres in the social deprivation of patients undergoing cataract surgery during the first year of the prospective national cataract audit, Figure 3. The IMD was not calculable for operations from the OpenEyes EMR or the centres using the inhouse data collection systems.

## 8.5 Preoperative Visual Acuity (Va)

A preoperative visual acuity was recorded for 97,196 (80.5%) eyes and missing for 23,526 (19.5%) eyes, of which 1,182 (1.0% of operations) had a Pin Hole Visual Acuity (PHVA) measured but no Corrected Distance Visual Acuity (CDVA) or Uncorrected Distance Visual Acuity (UDVA) measurement. There was wide variation in the percentage of eyes with missing preoperative VA by contributing centre, Figure 4. For the 97,196 eyes with a preoperative VA measurement, the measurement was CDVA in 67,911 (69.9%) eyes, UDVA in 27,832 (28.6%) eyes and in 1,453 (1.5%) eyes the CDVA measurement was the same as the UDVA measurement. The median preoperative VA was 0.50 LogMAR units (range; -0.30 - NPL) (6/19 Snellen Equivalent); where 3,472 (3.6%) eyes were CF, 1,888 (1.9%) eyes were HM, 465 (0.5%) eyes were PL and 37 (<0.1%) eyes were NPL. The preoperative VA was 0.30 LogMAR units (6/12) or better for 31,783 (32.7%) eyes, 0.60 LogMAR units (6/24) or better for 67,426 (69.4%) eyes and 1.0 LogMAR units (6/60) or better for 86,379 (88.9%) eyes. The median preoperative VA was 0.50 LogMAR units for each grade of surgeon. There was variability in the preoperative VA between contributing centres, although for the majority of centres the median preoperative VA was approximately 0.50 LogMAR units, Figure 5. Access to surgery, judged by preoperative VA was uniform regardless of IMD national decile, Figure 6. Preoperative VA is used as a proxy metric for access because where access to surgery is significantly limited the average preoperative VA would be expected to be worse and vice versa. For 15,703 patients who had both eyes undergo cataract surgery during the audit period and had a preoperative VA measurement for both eyes (excluding simultaneous bilateral surgery), the mean presenting VA was worse for the first treated eye than for the second treated eye (means = 0.60 (6/24) and 0.50 LogMAR (6/19) respectively, p < 0.001).

Of the 147 patients who had simultaneous bilateral surgery, 107 (72.8%) had presenting VA data for both eyes where the median difference in the VA between the right and left eyes was 0.00 LogMAR units and the inter quartile range was -0.10 - +0.10 LogMAR units.

## 8.6 Ocular Co-Pathology

The presence or absence of ocular co-pathology was recorded for 100% of operated eyes and was recorded as absent for 64,349 (53.3%) eyes, at least one ocular co-pathology was recorded for 56,373 (46.7%) eyes. The percentage of eyes reported to have an ocular co-pathology varied between participating centres, ranging from 14% to 96% and 10 centres had >50% of operated eyes with an ocular co-pathology, Figure 7. The centre with 96% of eyes with an ocular co-pathology utilises SNOMED-CT diagnosis coding which is more granular and hierarchical than The RCOphth NOD coding for ocular co-pathology. The RCOphth NOD is in communication with this centre with the aim of better matching the ocular co-pathology coding to SNOMED-CT diagnosis coding in future data extractions. The most commonly recorded ocular co-pathologies were 'unspecified other', age related macular degeneration, glaucoma and diabetic retinopathy which were recorded for 12.0%, 9.4%, 9.0% and 6.0% of operations respectively, Figure 8. 

A higher proportion of operations were performed by consultant surgeons for each individual ocular copathology, except for 'unspecified other' where a high proportion of these operations were performed by experienced trainee surgeons, although this result is heavily influenced by the centre with 96% of operations with 'unspecified other' as this centre also had a higher proportion of operations performed by experienced trainee surgeons, Figure 9. For the prospective data collection changes to the recording of ocular co-pathology were implemented, details about the impact of the changes on the ocular co-pathology results can be found in appendix 4.

## 8.7 Operation Characteristics

Phacoemulsification ± IOL was performed in all eligible cataract operations and for 116,612 (96.6%) operations was the only operative procedure performed. Phacoemulsification ± IOL was combined with one other procedure in 3,771 (3.1%) operations, with ≥2 other procedures in 339 (0.3%) operations. 

The most frequently performed operative procedures that were combined with phacoemulsification ± IOL were anterior vitrectomy and limbal relaxing incisions / Opposite Clear Corneal Incision (OCCI), which were performed in 0.8% and 0.5% of operations respectively. A full list of operative procedures combined with phacoemulsification ± IOL can be found in Appendix 5.

## 8.8 Operative Complications

One or more intra-operative complication was recorded for 3,924 (3.3%) operations, with the most frequently recorded being PCR which was reported for 1,821 (1.5%) operations. The 'any' intra-operative complication rates were higher for the less experienced grade of surgeons, while the rates for individual intra-operative complications were similar across the grades of surgeon except for PCR which was higher for the less experienced grades, Table 2.

Intra-operative complications n (column %)
Consultant surgeons (N = 74,228)
Career grade  
non-consultant surgeons (N = 13,219)
Eyes with no complications
72,194 (97.3)
12,828 (97.0)
27,665 (95.6)
4,111 (94.5)
116,798 (96.7)
Eyes with ≥1 complication
2,034 (2.7)
391 (3.0)
1,262 (4.4)
237 (5.5)
3,924 (3.3)
Recorded intra-operative complications*
Posterior capsular rupture
900 (1.2)
170 (1.3)
634 (2.2)
117 (2.7)
1,821 (1.5)
Zonule rupture - no 
vitreous loss
275 (0.4)
31 (0.2)
142 (0.5)
13 (0.3)
461 (0.4)
Corneal epithelial abrasion
203 (0.3)
58 (0.4)
83 (0.3)
29 (0.7)
373 (0.3)
Torn iris / damage from the phaco
138 (0.2)
24 (0.2)
74 (0.3)
17 (0.4)
253 (0.2)
Lens exchange required / other IOL problems
78 (0.1)
9 (<0.1)
41 (0.1)
17 (0.4)
145 (0.1)
Endothelial damage / Descemet's tear
70 (0.1)
18 (0.1)
43 (0.1)
13 (0.3)
144 (0.1)
Anterior capsular tear
45 (<0.1)
3 (<0.1)
86 (0.3)
0 (0.0)
134 (0.1)
Corneal oedema
74 (0.1)
13 (0.1)
30 (0.1)
7 (0.2)
124 (0.1)
Iris trauma
22 (<0.1)
9 (<0.1)
38 (0.1)
1 (<0.1)
70 (<0.1)
Hyphaema
34 (<0.1)
5 (<0.1)
17 (<0.1)
4 (0.1)
60 (<0.1)
Iris prolapse
22 (<0.1)
3 (<0.1)
32 (0.1)
1 (<0.1)
58 (<0.1)
Phaco burn / wound problems
20 (<0.1)
4 (<0.1)
21 (<0.1)
3 (<0.1)
48 (<0.1)
Choroidal / suprachoroidal haemorrhage
32 (<0.1)
4 (<0.1)
7 (<0.1)
0 (0.0)
43 (<0.1)
Unspecified other**
279 (0.4)
65 (0.5)
121 (0.4)
33 (0.8)
498 (0.4)

*Each operation can have more than one intra-operative complication recorded. **The unspecified other included one vitreous haemorrhages and nine instances when the operation was cancelled. 

Total (N = 120,722)
Experienced trainee surgeons (N = 28,927)
Less experienced trainee surgeons (N = 4,348)

## 8.9 Postoperative Complications

Of the 120,722 eligible cataract operations submitted to the audit, 99,087 (82.1%) operations were performed before 30th June 2016 and had the potential for two months follow up. Of these 63,806 (64.4%) operations had no postoperative complication data recorded, 31,246 (31.5%) had 'none' recorded as the postoperative complication and 4,035 (4.1%) had at least one postoperative complication recorded. The percentage of operations with a postoperative complication record (none or a complication) or no postoperative complication record varied significantly between the participating centres, with seven centres having no records of any specific postoperative complications, Figure 10. The most frequently recorded postoperative complication was postoperative uveitis which was the only individual postoperative complication recorded for >1.0% of operations, Figure 11.

## 8.10 Postoperative Visual Acuity

Of the 120,722 eligible cataract operations submitted to the audit, 99,087 (82.1%) operations were performed before 30th June 2016 and had the potential for two months follow up. Of these a postoperative visual acuity was recorded for 66,769 (67.4%) eyes and missing for 32,318 (32.6%) eyes. There was wide variation in the percentage of eyes with missing postoperative VA by contributing centre, Figure 12, although influencing this result are operations performed in the latter part of the audit period where follow up times may have been too brief for all post op results to be available. For the 66,769 eyes with a postoperative VA measurement, the best measurement was CDVA in 21,752 (32.6%) eyes, UDVA in 18,978 (28.4%) eyes, PHVA in 14,338 (21.5%) eyes; the best measurement was the same for two of the assessment methods for 10,768 (16.1%) eyes and the same for all three methods in 933 (1.4%) eyes. The median postoperative VA was 0.10 LogMAR units (range; -0.30 - NPL) (6/7.5 Snellen equivalent); where 217 (0.3%) eyes were CF, 136 (0.2%) eyes were HM, 35 (<0.1%) eyes were PL and 13 (<0.1%) eyes were NPL. The postoperative VA was 0.30 LogMAR units (6/12) or better for 59,047 (88.4%) eyes, 0.60 LogMAR units (6/24) or better for 64,007 (95.9%) eyes and 1.0 LogMAR units (6/60) or better for 65,773 (98.5%) eyes. The postoperative VA was fairly stable across participating centres, Figure 13. 

## 8.11 Change In Visual Acuity

Of the 99,087 eligible cataract operations submitted to the audit performed before 30th June 2016, 56,588 (57.1%) eyes had both a preoperative VA and a postoperative VA measurement. The median change in VA from baseline was a 0.38 LogMAR gain (IQR; 0.20 - 0.60 gain). The change in VA was fairly stable between the participating centres, Figure 14. 74% of eyes with a presenting VA of 0.00 LogMAR or better had a postoperative VA of 0.00 LogMAR or better and 97% of eyes with a presenting VA of 0.30 LogMAR or better had a postoperative VA of 0.30 LogMAR or better. Eyes that had an ocular co-pathology or experienced an intra-operative complication or PCR during surgery had worse postoperative VA than eyes that did not have any of these problems. >88% of eyes without these problems had a postoperative VA of 0.30 LogMAR (6/12 Snellen) or better, Table 3. The percentage of operations from each participating centre with preoperative VA, postoperative VA and both pre- and postoperative VA data varied between participating centres, Table 4.

Post-operative LogMAR visual acuity
Percentages are row % (Approximate Snellen)
≤0.00  
(6/6 or better)
≤0.18  
(6/9 or better)
All eyes (N = 56,588)
39.0
59.0
88.6
95.9
98.5
Presenting LogMAR VA (Snellen)
≤0.00 (N = 1,068)
74.3
84.6
98.6
99.6
99.9
≤0.18 (N = 2,486)
62.6
85.5
97.9
99.6
99.9
≤0.30 (N = 17,870)
49.6
69.2
96.7
99.5
99.9
≤0.60 (N = 38,886)
41.9
63.0
93.4
99.1
99.9
≤1.00 (N = 50,283)
40.2
60.8
90.8
97.7
99.6
Ocular co-pathology
No (N = 30,296)
45.9
65.4
94.8
98.9
99.7
Yes (N = 26,292)
31.0
51.6
81.4
92.3
97.1
Intra-operative complications
No (N = 54,880)
39.4
59.5
88.9
96.1
98.6
Yes (N = 1,708)
25.2
43.5
76.9
89.3
95.5
PCR
No (N = 55,791)
39.2
59.3
88.8
96.0
98.6
Yes (N = 797)
19.9
37.8
70.9
84.2
92.3
≤0.30   
(6/12 or 
better)
≤0.60  
(6/24 or 
better)
≤1.00  
(6/60 or 
better)
Centre name
Centre 
number
Number of 
operations
% with 
preoperative 
VA data
Moorfields Eye Hospital NHS Foundation Trust (Open Eyes Centre)
1
10,626
55.87
8,713
56.51
45.33
The Newcastle upon Tyne Hospitals NHS Foundation Trust
2
7,560
90.25
6,136
82.97
75.70
Norfolk and Norwich 
University Hospitals NHS 
Foundation Trust
3
4,639
91.21
3,786
12.60
11.52
Leeds Teaching Hospitals NHS Trust
4
4,371
87.19
3,582
81.24
72.19
York Teaching Hospital NHS Foundation Trust (In-house database)
5
4,212
37.77
3,630
0.19
0.11
Oxford University Hospitals NHS Foundation Trust
6
4,182
82.47
3,507
60.99
51.98
University Hospitals Bristol NHS Foundation Trust
7
4,154
83.32
3,471
81.96
70.61
Gloucestershire Hospitals NHS Foundation Trust
8
4,085
69.08
3,415
92.12
63.48
Sheffield Teaching Hospitals NHS Foundation Trust
9
3,829
92.37
3,439
76.59
70.92
Sandwell and West Birmingham Hospitals NHS Trust
10
3,332
79.83
2,848
87.18
69.91
University Hospital Southampton NHS Foundation Trust
11
3,128
85.49
2,563
79.24
67.19
Royal Berkshire NHS Foundation Trust
12
3,109
94.40
2,559
85.81
80.70
Calderdale and Huddersfield NHS Foundation Trust
13
2,864
72.73
2,299
71.77
53.41
Mid Cheshire Hospitals NHS Foundation Trust
14
2,637
91.81
2,209
70.85
64.78
The Mid Yorkshire Hospitals NHS Trust
15
2,615
41.91
2,217
78.98
33.51
Cardiff & Vale University LHB
16
2,414
92.13
2,014
35.40
31.73
Epsom and St Helier University Hospitals NHS Trust
17
2,406
87.03
2,065
88.43
77.24
% with 
postoperative 
VA data
% with 
change 
in VA 
data
Number of 
operations 
eligible for 
postoperative VA 
results
Centre name
Centre 
number
Number of 
operations
% with 
preoperative 
VA data
Barts Health NHS Trust
18
2,376
84.47
1,965
72.88
60.97
Frimley Health NHS Foundation Trust
19
2,290
95.85
1,875
43.47
42.19
Bradford Teaching Hospitals NHS Foundation Trust
20
2,268
68.39
1,907
30.83
21.97
Moorfields Eye Centre 
at Bedford Hospital NHS Trust
21
2,257
89.94
1,877
90.84
81.14
Plymouth Hospitals NHS Trust
22
2,223
93.97
1,866
64.42
61.84
University Hospitals Birmingham NHS Foundation Trust
23
1,977
89.02
1,629
92.27
82.07
Hampshire Hospitals NHS Foundation Trust
24
1,975
84.30
1,632
79.29
65.50
Royal Cornwall Hospitals NHS Trust
25
1,969
91.62
1,629
70.60
65.93
Central Manchester University Hospitals NHS Foundation Trust
26
1,952
95.85
1,601
92.25
88.26
King's College Hospital NHS Foundation Trust
27
1,924
79.68
1,489
77.43
59.57
Shrewsbury and Telford Hospital NHS Trust
28
1,920
83.44
1,585
75.96
65.30
Moorfields Eye Centre at Croydon Health Services NHS Trust
29
1,824
98.52
1,534
87.35
86.18
The Hillingdon Hospitals NHS Foundation Trust
30
1,693
74.19
1,358
88.37
63.92
Aintree University Hospital NHS Foundation Trust
31
1,626
82.04
1,366
74.89
60.18
Royal United Hospitals Bath NHS Foundation Trust
32
1,597
76.21
1,304
49.39
37.88
Chesterfield Royal Hospital NHS Foundation Trust
33
1,472
80.30
1,190
95.88
80.84
Mid Essex Hospital Services NHS Trust
34
1,462
90.29
1,203
69.33
63.01
% with 
postoperative 
VA data
% with 
change 
in VA 
data
Number of 
operations 
eligible for 
postoperative 
VA results
Centre name
Centre 
number
Number of 
operations
% with 
preoperative 
VA data
Harrogate and District NHS Foundation Trust
35
1,461
88.57
1,194
84.92
74.54
Hinchingbrooke Health Care NHS Trust
36
1,458
97.26
1,232
89.77
87.58
Northern Devon Healthcare NHS Trust
37
1,431
89.80
1,225
87.43
78.78
Peterborough and 
Stamford Hospitals NHS Foundation Trust
38
1,402
87.66
1,212
73.93
65.18
Wirral University Teaching Hospital NHS Foundation Trust
39
1,351
68.62
1,221
49.96
35.30
South Warwickshire NHS Foundation Trust
40
1,286
82.27
1,080
77.50
64.81
Isle of Wight NHS Trust
41
1,222
77.25
1,055
79.62
61.61
St Helens and Knowsley Teaching Hospitals NHS Trust
42
1,135
86.96
896
51.56
44.75
Wrightington, Wigan and Leigh NHS Foundation Trust
43
993
96.07
731
70.73
68.81
Warrington and Halton Hospitals NHS Foundation Trust
44
855
96.02
533
6.38
6.00
South Tees Hospitals NHS Foundation Trust
45
687
91.27
555
51.17
46.31
46
574
95.64
343
69.68
67.93
The Royal Bournemouth and Christchurch Hospitals NHS Foundation Trust
Barking, Havering and Redbridge University Hospitals NHS Trust
47
568
87.15
452
25.22
23.01
Royal Free London NHS Foundation Trust
48
552
92.21
262
10.69
9.54
University Hospitals Coventry and Warwickshire NHS Trust
49
551
91.29
338
21.01
20.41
Barnsley Hospital NHS Foundation Trust (Inhouse database)
50
458
53.93
212
30.19
22.17
% with 
postoperative 
VA data
% with 
change 
in VA 
data
Number of 
operations 
eligible for 
postoperative 
VA results
Centre name
Centre 
number
Number of 
operations
% with 
preoperative 
VA data
Salisbury NHS Foundation Trust
51
453
94.26
156
87.18
82.05
London North West Healthcare NHS Trust (In-house database)
52
325
58.46
266
23.31
15.04
Blackpool Teaching 
Hospitals NHS 
Foundation Trust
53
297
56.23
295
46.44
27.46
University Hospitals of Morecambe Bay NHS Foundation Trust
54
288
56.60
190
17.89
14.21
Nottingham University Hospitals NHS Trust
55
250
74.00
113
80.53
58.41
Yeovil District Hospital NHS Foundation Trust
56
157
98.73
63
46.03
44.44

## 8.12 Case Complexity Adjusted Pcr Results

Unadjusted for case complexity PCR rates for 54 of the 56 participating centres are shown on Figure 15 and an adjusted for case complexity graph in Figure 16. Two centres data is not reported as they have requested that their data is not published while they carry out internal investigations into the data collection at their sites. Details of the unadjusted and adjusted for case complexity PCR results for 54 participating centres can be found in Table 5.

% with 
postoperative 
VA data
% with 
change 
in VA 
data
Number of 
operations 
eligible for 
postoperative 
VA results
|                                                Posterior Capsular rupture   | Visual Acuity loss   |
|-----------------------------------------------------------------------------|----------------------|
| Centre name                                                                 | Centre               |
| number                                                                      |                      |
| Number of                                                                   |                      |
| operations                                                                  |                      |
| Unadjusted                                                                  |                      |
| PCR rate                                                                    |                      |
| (%)                                                                         |                      |
| Adjusted                                                                    |                      |
| PCR rate                                                                    |                      |
| (%)                                                                         |                      |
| 1                                                                           | 10,626               |
| Hospital NHS                                                                |                      |
| Foundation Trust (OE)                                                       |                      |
| 2                                                                           | 7,560                |
| Tyne Hospitals NHS                                                          |                      |
| Foundation Trust                                                            |                      |
| 3                                                                           | 4,639                |
| University Hospitals                                                        |                      |
| NHS Foundation Trust                                                        |                      |
| Leeds Teaching                                                              |                      |
| Hospitals NHS Trust                                                         |                      |
| 4                                                                           | 4,371                |
| York Teaching Hospital                                                      |                      |
| NHS Foundation Trust                                                        |                      |
| 5                                                                           | 4,212                |
| 6                                                                           | 4,182                |
| Hospitals NHS                                                               |                      |
| Foundation Trust                                                            |                      |
| 7                                                                           | 4,154                |
| Bristol NHS                                                                 |                      |
| Foundation Trust                                                            |                      |
| 8                                                                           | 4,085                |
| Hospitals NHS                                                               |                      |
| Foundation Trust                                                            |                      |
| 9                                                                           | 3,829                |
| Hospitals NHS                                                               |                      |
| Foundation Trust                                                            |                      |
| 11                                                                          | 3,128                |
| Southampton NHS                                                             |                      |
| Foundation Trust                                                            |                      |
| Royal Berkshire NHS                                                         |                      |
| Foundation Trust                                                            |                      |
| 12                                                                          | 3,109                |
| 13                                                                          | 2,864                |
| Huddersfield NHS                                                            |                      |
| Foundation Trust                                                            |                      |
| Mid Cheshire Hospitals                                                      |                      |
| NHS Foundation Trust                                                        |                      |
| 14                                                                          | 2,637                |
| The Mid Yorkshire                                                           |                      |
| Hospitals NHS Trust                                                         |                      |
| 15                                                                          | 2,615                |
| Cardiff & Vale                                                              |                      |
| University LHB                                                              |                      |
| 16                                                                          | 2,414                |
| 17                                                                          | 2,406                |
| University Hospitals                                                        |                      |
| NHS Trust                                                                   |                      |
| Barts Health NHS Trust                                                      | 18                   |
| Frimley Health NHS                                                          |                      |
| Foundation Trust                                                            |                      |
| 19                                                                          | 2,290                |
| 20                                                                          | 2,268                |
| Hospitals NHS                                                               |                      |
| Foundation Trust                                                            |                      |
| 21                                                                          | 2,257                |
| at Bedford Hospital                                                         |                      |
| NHS Trust                                                                   |                      |
Adjusted VA 
Loss rate (%)
Outlier
Outlier
Number of 
operations
Unadjusted 
VA Loss 
rate (%)
|                                                Posterior Capsular rupture   | Visual Acuity loss   |
|-----------------------------------------------------------------------------|----------------------|
| Centre name                                                                 | Centre               |
| number                                                                      |                      |
| Number of                                                                   |                      |
| operations                                                                  |                      |
| Unadjusted                                                                  |                      |
| PCR rate                                                                    |                      |
| (%)                                                                         |                      |
| Adjusted                                                                    |                      |
| PCR rate                                                                    |                      |
| (%)                                                                         |                      |
| Plymouth Hospitals                                                          |                      |
| NHS Trust                                                                   |                      |
| 22                                                                          | 2,223                |
| 23                                                                          | 1,977                |
| Birmingham NHS                                                              |                      |
| Foundation Trust                                                            |                      |
| Hampshire Hospitals                                                         |                      |
| NHS Foundation Trust                                                        |                      |
| 24                                                                          | 1,975                |
| Royal Cornwall                                                              |                      |
| Hospitals NHS Trust                                                         |                      |
| 25                                                                          | 1,969                |
| 26                                                                          | 1,952                |
| University Hospitals                                                        |                      |
| NHS Foundation Trust                                                        |                      |
| King's College Hospital                                                     |                      |
| NHS Foundation Trust                                                        |                      |
| 27                                                                          | 1,924                |
| Shrewsbury and Telford                                                      |                      |
| Hospital NHS Trust                                                          |                      |
| 28                                                                          | 1,920                |
| 29                                                                          | 1,824                |
| at Croydon Health                                                           |                      |
| Services NHS Trust                                                          |                      |
| 30                                                                          | 1,693                |
| Hospitals NHS                                                               |                      |
| Foundation Trust                                                            |                      |
| 31                                                                          | 1,626                |
| Hospital NHS                                                                |                      |
| Foundation Trust                                                            |                      |
| 32                                                                          | 1,597                |
| Bath NHS Foundation                                                         |                      |
| Trust                                                                       |                      |
| 33                                                                          | 1,472                |
| Hospital NHS                                                                |                      |
| Foundation Trust                                                            |                      |
| Harrogate and District                                                      |                      |
| NHS Foundation Trust                                                        |                      |
| 35                                                                          | 1,461                |
| Hinchingbrooke                                                              |                      |
| Health Care NHS Trust                                                       |                      |
| 36                                                                          | 1,458                |
| Northern Devon                                                              |                      |
| Healthcare NHS Trust                                                        |                      |
| 37                                                                          | 1,431                |
| 38                                                                          | 1,402                |
| Stamford Hospitals                                                          |                      |
| NHS Foundation Trust                                                        |                      |
| 39                                                                          | 1,351                |
| Teaching Hospital                                                           |                      |
| NHS Foundation Trust                                                        |                      |
| South Warwickshire                                                          |                      |
| NHS Foundation Trust                                                        |                      |
| 40                                                                          | 1,286                |
| Isle of Wight NHS Trust                                                     | 41                   |
| 42                                                                          | 1,135                |
| Knowsley Teaching                                                           |                      |
| Hospitals NHS Trust                                                         |                      |
Adjusted VA 
Loss rate (%)
Outlier
Outlier
Number of 
operations
Unadjusted 
VA Loss 
rate (%)
|                                                Posterior Capsular rupture   | Visual Acuity loss   |
|-----------------------------------------------------------------------------|----------------------|
| Centre name                                                                 | Centre               |
| number                                                                      |                      |
| Number of                                                                   |                      |
| operations                                                                  |                      |
| Unadjusted                                                                  |                      |
| PCR rate                                                                    |                      |
| (%)                                                                         |                      |
| Adjusted                                                                    |                      |
| PCR rate                                                                    |                      |
| (%)                                                                         |                      |
| 43                                                                          | 993                  |
| and Leigh NHS                                                               |                      |
| Foundation Trust                                                            |                      |
| 44                                                                          | 855                  |
| Halton Hospitals NHS                                                        |                      |
| Foundation Trust                                                            |                      |
| South Tees Hospitals                                                        |                      |
| NHS Foundation Trust                                                        |                      |
| 45                                                                          | 687                  |
| 46                                                                          | 574                  |
| Bournemouth and                                                             |                      |
| Christchurch Hospitals                                                      |                      |
| NHS Foundation Trust                                                        |                      |
| 47                                                                          | 568                  |
| Redbridge University                                                        |                      |
| Hospitals NHS Trust                                                         |                      |
| Royal Free London                                                           |                      |
| NHS Foundation Trust                                                        |                      |
| 48                                                                          | 552                  |
| 49                                                                          | 551                  |
| Coventry and                                                                |                      |
| Warwickshire NHS                                                            |                      |
| Trust                                                                       |                      |
| Barnsley Hospital NHS                                                       |                      |
| Foundation Trust                                                            |                      |
| 50                                                                          | 458                  |
| Salisbury NHS                                                               |                      |
| Foundation Trust                                                            |                      |
| 51                                                                          | 453                  |
| London North West                                                           |                      |
| Healthcare NHS Trust                                                        |                      |
| 52                                                                          | 325                  |
| 53                                                                          | 297                  |
| Hospitals NHS                                                               |                      |
| Foundation Trust                                                            |                      |
| 54                                                                          | 288                  |
| Morecambe Bay NHS                                                           |                      |
| Foundation Trust                                                            |                      |
| 55                                                                          | 250                  |
| University Hospitals                                                        |                      |
| NHS Trust                                                                   |                      |
| Yeovil District Hospital                                                    |                      |
| NHS Foundation Trust                                                        |                      |
| 56                                                                          | 157                  |
Adjusted VA 
Loss rate (%)
Outlier
Outlier
Number of 
operations
Unadjusted 
VA Loss 
rate (%)

## 8.13 Case Complexity Adjusted Visual Loss Results

Of the 120,722 operations supplied to the audit, 99,087 operations were performed up to 30th June 2016 and had the potential for two months follow up. Of these, 43,566 (44.0%) operations from 32 centres were performed in centres where a preoperative and postoperative VA was recorded for at least 40% of the operations. An unadjusted for case complexity funnel plot of VA Loss is shown in Figure 17 and an adjusted for case complexity funnel plot in Figure 18 for 30 of the 32 centres with VA Loss data. Two centres data is not reported as they have requested that their data is not published while they carry out internal investigations into the data collection at their sites. Details of the unadjusted and adjusted for case complexity VA Loss results for the 30 participating centres can be found in Table 5. For 19 of the 30 centres, the case complexity adjusted VA rate was below the benchmark mean of 1.5% 
derived from earlier sets of data. There are likely to be many reasons for this result. The actual observed overall visual loss rate was 0.81% for this sample which is lower than the benchmark used, and there is variation in the number of operations and the number/experience of surgeons between centres. Some centres will have fewer surgeons than others and if these surgeons are very experienced this will contrast with a teaching hospital that is likely to have more operations performed by relatively less experienced surgeons. Another influence is the variation in the recording of follow up data which is necessary for visual loss estimation. In light of this apparent reduction in the rate of Visual Acuity Loss the benchmark rate will need to be reconsidered for future audit cycles although until fuller data return completeness is achieved caution should be exercised. It should also be noted that the samples used for the VA Loss results are smaller than those used for the PCR results due to missing presenting and/or postoperative VA measurements. Any improvements in the number of operations with a recorded presenting and postoperative VA would increase the sample for future re-fitting of the Visual Loss model, this in turn would decrease parameter estimation errors due to the increased sample size.

## 9. Summary Of Key Points

This second annual report from the National Ophthalmology Database Cataract Audit is the first to report prospectively collected data for a one year period. 

- Good progress has been made in terms of expanding the number of centres from 34 in the first 
annual report to 56 in the current report and looking ahead 112 of 125 traditional NHS cataract providers have indicated that they wish to participate in the future cycles of the audit. 
- Established markers of surgical quality - PCR and VA Loss - are used as metrics for risk adjusted  
outcomes. PCR is the most frequent intra-operative complication and is associated with postoperative loss of vision. VA Loss is intended to capture all eyes where outcome has been adverse whether or not associated with PCR. 
- This is the first cataract audit report which includes the reporting of named centre results for all  
submitted operations with results for named consultant surgeons shortly to be published as part of the Consultants Outcomes Programme (COP). For the 56 centres included in this report outcomes generally have been found to be within the standard HQIP expectation, i.e. risk adjusted outcomes within 3SD of the benchmark. 
- Data completeness of reported surgery is excellent (100%) for PCR though less so for VA, particularly  
for postoperative VA, an area where many centres could do better, some centres in particular having poor VA data returns following surgery. 
- Quality improvement drivers in this audit take the form of risk adjusted results for surgical 
complications and vision loss from before to after surgery. These key measures are risk adjusted to acknowledge case complexity and provide credit to surgeons and centres undertaking complex work. Without conscious completion of risk indicator data surgeons and centres run the risk of not being given credit for the complexity of the work undertaken, an important message for participants to take on board. 
- The audit tools provided allow for real time tracking of adverse surgical events which facilitates local  
monitoring of complications by centres and surgeons. In the event of an adverse signal becoming apparent, timely corrective action would avoid unnecessary harm to patients and avoid centres or surgeons being identified as outliers in national audit reports going forward. 
The coming period of the audit will look to extending the coverage to include all traditional NHS centres as well as the 'independent sector treatment centres', all of which are accountable to the public for the quality of services they provide. In addition, further outcomes will be considered in order to provide a broader and more balanced assessment of service quality in cataract care. 

## 10. Glossary

| Abbreviation                                                                                  | Description                                                                             |
|-----------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------|
| CDVA                                                                                          | Corrected distance visual acuity                                                        |
| CF                                                                                            | The ability to count fingers                                                            |
| EMR                                                                                           | Electronic Medical Record                                                               |
| HM                                                                                            | The ability to distinguish hand movements                                               |
| HQIP                                                                                          | Healthcare Quality Improvement Partnership                                              |
| HSCIC                                                                                         | Health and Social Care Information Centre                                               |
| IMD                                                                                           |                                                                                         |
| Index of multiple deprivation is the measure of relative deprivation for small areas in       |                                                                                         |
| England                                                                                       |                                                                                         |
| IOL                                                                                           |                                                                                         |
| Intra-ocular lens is an artificial lens generally inserted into the capsule of the lens after |                                                                                         |
| cataract removal                                                                              |                                                                                         |
| IQR                                                                                           | Inter Quartile Range                                                                    |
| OCCI                                                                                          | Opposite Clear Corneal Incision                                                         |
| NCAPOP                                                                                        | National Clinical Audit and Patient Outcomes Programme                                  |
| NICOR                                                                                         | National Institute for Cardiovascular Outcomes Research                                 |
| NHS                                                                                           | National Health Service                                                                 |
| NOD                                                                                           | National Ophthalmology Database                                                         |
| NPL                                                                                           | No perception of light                                                                  |
| PAS                                                                                           | Patient Administration System keeps track of all patients' admissions and appointments. |
| PCR                                                                                           |                                                                                         |
| Posterior capsule rupture is a break in the posterior capsule of the lens, usually as a       |                                                                                         |
| complication of cataract surgery.  It may allow vitreous to move forward into the anterior    |                                                                                         |
| chamber of the eye.                                                                           |                                                                                         |
| PHVA                                                                                          |                                                                                         |
| Pin hole visual acuity - The pinhole is an eye shield with several small holes which allow    |                                                                                         |
| light rays to reach the retina without the interference of optical problems of the eye. It is |                                                                                         |
| used to test visual acuity.                                                                   |                                                                                         |
| PL                                                                                            | Perception light                                                                        |
| RCOphth                                                                                       | The Royal College of Ophthalmologists                                                   |
| S251 exemption                                                                                |                                                                                         |
| Approval for exemption from section 251 of the NHS Health and Social Care Act 2006            |                                                                                         |
| which allows for certain uses of patient identifiable data such as linkage of data from more  |                                                                                         |
| than one data source e.g. a national audit and NHS Digital                                    |                                                                                         |
| SES                                                                                           |                                                                                         |
| Socio-economic status is the social standing or class of an individual or group.              |                                                                                         |
| It is often measured as a combination of education, income and occupation                     |                                                                                         |
| UDVA                                                                                          | Uncorrected distance visual acuity                                                      |

## 10. Glossary Continued

| Abbreviation                                                                                | Description               |
|---------------------------------------------------------------------------------------------|---------------------------|
| UK                                                                                          | United Kingdom            |
| VA                                                                                          |                           |
| Visual acuity is the sharpness of vision, measured by the ability to distinguish letters or |                           |
| numbers at a given distance according to a fixed standard. We have reported VA using the    |                           |
| LogMAR scale (base 10 Log of the reciprocal of the visual angle). A normal LogMAR VA is     |                           |
| 0.0 and the number increases as vision gets worse. LogMAR=0.3 would be at the boundary      |                           |
| for driving a car and 1.0 would be at the level of registrable severe sight impairment. A   |                           |
| postoperative VA of 0.3 or better                                                           |                           |
| is often used as a measure of a favourable outcome from surgery.                            |                           |
| WHO                                                                                         | World Health Organisation |
| Yes/No                                                                                      | Yes or No                 |

## 11. Graphs And Tables Interpreting The Graphs

Among the results there are three types of graphs. The labelling of centres is a ranking of the total number of operations contributed by each centre so that centre 1 is the centre that contributed the highest number of operations and centre 56 the least.

1.	 
Bar charts - the horizontal axis consists of the categorical element, usually contributing centre. When bar charts are sub-divided by another category, the vertical height of each bar indicates the quantity of interest for that bar chart as read from the vertical axis.
2.	 
Box and Whisker plots - the spread for the variable of interest is shown for each of the contributing centres. The central line is the median or 'middle' value. The box outlines the inter quartile range (25% 
and 75% centiles), and the horizontal lines above and below the inter quartile range display either the 
position of the furthest value or a value at a 'reasonable' stretch from the middle. Extreme values are the dots beyond that. 
3.	 
Funnel plots - The spread of dots on these look like a funnel going from left to right. Each dot represents a result for a centre as read off the vertical axis (proportion or rate). The funnel effect results from increasing statistical precision as the numbers get higher going along the horizontal axis. Some of the plots have lines on them showing what is expected. A result above the top line (three standard deviations) would be deemed unacceptably high. 

## 12. References

1.	 
Sparrow JM, Taylor H, Qureshi K, Smith R, Birnie K, Johnston RL; UK EPR user group. The Cataract National Dataset electronic multi-centre audit of 55,567 operations: risk indicators for monocular visual acuity outcomes. Eye (Lond). 2012 Jun;26(6):821-6
2.	 Sparrow JM, Taylor H, Qureshi K, Smith R, Johnston RL. The cataract national data set electronic 
multi-centre audit of 55,567 operations: case-mix adjusted surgeon's outcomes for posterior capsular  
	
rupture. Eye 2011 May Eye 2011, 1–6
3.	 Johnston RL, Taylor H, Smith R, Sparrow JM. The Cataract National Dataset electronic multi-centre 
audit of 55,567 operations: variation in posterior capsule rupture rates between surgeons. Eye (Lond).  
	
2010 May; 24(5):888-93.
4.	 Knox Cartwright NE, Johnston RL, Jaycock PD, Tole DM, Sparrow JM. The Cataract National Dataset 
electronic multicentre audit of 55,567 operations: when should IOLMaster biometric measurements  
	
be rechecked? Eye (Lond). 2010 May; 24(5):894-900.
5.	 Narendran N, Jaycock P, Johnston RL, Taylor H, Adams M, Tole DM, Asaria RH, Galloway P, Sparrow 
JM. The Cataract National Dataset electronic multicentre audit of 55,567 operations: risk stratification  
	
for posterior capsule rupture and vitreous loss. Eye (Lond). 2009 Jan; 23(1):31-7. 
6.	 Jaycock P, Johnston RL, Taylor H, Adams M, Tole DM, Galloway P, Canning C, Sparrow JM; UK EPR 
user group. The Cataract National Dataset electronic multi-centre audit of 55,567 operations:  
	
updating benchmark standards of care in the United Kingdom and internationally. Eye (Lond).  
	
2009 Jan; 23(1):38-49.
7.	 El-Hindy N, Johnston RL, Jaycock P, Eke T, Braga AJ, Tole DM, Galloway P, Sparrow JM; UK EPR user 
group. The Cataract National Dataset Electronic Multi-centre Audit of 55,567 operations: anaesthetic  
	
techniques and complications. Eye (Lond). 2009 Jan; 23(1):50-5. Epub 2008 Mar 14
8.	 Benzimra JD, Johnston RL, Jaycock P, Galloway PH, Lambert G, Chung AK, Eke T, Sparrow JM; EPR User  
	
Group. The Cataract National Dataset electronic multicentre audit of 55,567 operations: antiplatelet  
	
and anticoagulant medications. Eye (Lond). 2009 Jan; 23(1):10-6. Epub 2008 Feb 8.
9.	 Johnston RL, Sparrow JM, Canning CR, Tole D, Price NC. Pilot National Electronic Cataract Surgery 
Survey: I. Method, descriptive, and process features. Eye (Lond). 2005 Jul; 19(7):788-94.
10.	English index of multiple deprivation, https://data.gov.uk/dataset/index-of-multiple-deprivation

## Appendix 1: Governance Structure National Ophthalmology Database (Nod) Audit Project Data Flow Appendix 2: National Ophthalmology Database Audit Project Steering Group Membership

| Name                                                            | Designation                                   |
|-----------------------------------------------------------------|-----------------------------------------------|
| Andrew Frost                                                    | Cataract Representative                       |
| The Royal College of Ophthalmologists                           |                                               |
| Anthony King                                                    | Glaucoma Representative                       |
| The Royal College of Ophthalmologists                           |                                               |
| Beth Barnes                                                     | Head of the Professional Standards Department |
| The Royal College of Ophthalmologists                           |                                               |
| Cathy Yelf                                                      | Chief Executive                               |
| Macular Society                                                 |                                               |
| Chris Rogers                                                    | Independent Statistician                      |
| The University of Bristol                                       |                                               |
| David Parkins                                                   | Immediate Past President                      |
| The College of Optometrists                                     |                                               |
| David Yorston                                                   | Retinal Detachment Representative             |
| The Royal College of Ophthalmologists                           |                                               |
| Helen Doe                                                       | Ophthalmic Nurse and Support Groups Manager   |
| International Glaucoma Association                              |                                               |
| Jessica Hall                                                    | Acting Eye Health Campaigns Manager           |
| Royal National Institute of Blind People                        |                                               |
| John Sparrow                                                    | Chairman                                      |
| Clinical Lead for RCOphth National Ophthalmology Database Audit |                                               |
| Kathy Evans                                                     | Chief Executive                               |
| The Royal College of Ophthalmologists                           |                                               |
| Martin McKibbin                                                 | AMD Representative                            |
| The Royal College of Ophthalmologists                           |                                               |
| Matt Broom                                                      | Lay Group Representative                      |
| The Royal College of Ophthalmologists and Vision 2020 UK        |                                               |
| Melanie Hingorani                                               | Cataract Representative                       |
| The Royal College of Ophthalmologists                           |                                               |
| Raghu Ram                                                       | Wales Representative                          |
| The Royal College of Ophthalmologists                           |                                               |
| Sasha Hewitt                                                    | Associate Director of Quality and Development |
| Healthcare Quality Improvement Partnership (HQIP)               |                                               |
| Sophia Olatunde                                                 | Project Manager                               |
| Healthcare Quality Improvement Partnership (HQIP)               |                                               |
| Wendy Newsom                                                    | Practicing Optometrist                        |
| The College of Optometrists                                     |                                               |

## Appendix 3: Case Definitions Eligible Cataract Surgery Criteria

- Operation performed between 01 September 2015 - 31 August 2016 - Operation performed in an NHS hospital in England or Wales - Operation performed in adults (aged 18 or above - Operation included a phacoemulsification procedure - Operative data includes a surgeon identifier and valid surgeon grade - Operation included a "cataract" indication for surgery (see the NOD audit website for details) - Operation did not include certain operative procedures (see the NOD audit website for details)
- Operations that included a pars plana vitrectomy without any other vitreoretinal procedures
- A minimum of 50 eligible cataract operations for each participated centre

## Pcr - Posterior Capsule Rupture Or Vitreous Prolapse Or Both

PCR was deemed to have occurred if any of the following intra-operative complications are recorded during surgery; Zonule rupture - vitreous loss, PC rupture ± vitreous loss, Vitreous to the section at end of surgery, Vitreous loss, Nuclear/ epinuclear fragment into vitreous, intra-ocular lens (IOL) into the vitreous, or if any of the following occurred.

- The operation includes any of 'Sponge and scissors vitrectomy', 'Secondary IOL', 'Automated anterior 
vitrectomy' or 'Scleral fixed IOL'
- The operative procedure includes 'Fragmatome lensectomy ± IOL' with a previous or concurrent 
phacoemulsification procedure
- The operative procedure includes 'Removal of retained lens fragments' combined with a pars plana 
vitrectomy
- If either of 'vitreous to the section' or 'vitreous in the anterior chamber' were recorded within eight 
weeks of cataract surgery, this includes the day of cataract surgery in the time frame
- If there is a record of a dropped nucleus operation with 90 days of cataract surgery, this includes the 
day of cataract surgery in the time frame

## Visual Acuity (Va) Criteria

Visual acuity measurements were extracted from the EMR on the LogMAR scale and numeric substitutions of 2.10, 2.40, 2.70 and 3.00 were used for the ability to count fingers (CF), the ability to distinguish hand movements (HM), perception of light (PL) and no perception of light (NPL) respectively. Pre-operative VA was defined as the better of corrected distance visual acuity (CDVA) and the uncorrected distance visual acuity (UDVA) recorded within a 90 day 'time window' prior to surgery. Where there are multiple occasions of measurement the VA measurement closest to the date of surgery is used and measurements recorded on the same day as cataract surgery are considered as pre-operative measurements. Postoperative VA was defined as the best measurement of CDVA or UDVA or pinhole visual acuity (PHVA) within the 'time window' of between 14 days and four months of cataract surgery (inclusive).

## Appendix 3: Case Definitions Continued

Postoperative VA results were restricted to operations performed up to 30th June 2016 to allow for at least two months potential follow up. A further restriction was applied to the VA Loss results where only centres and surgeons with <40% missing pre and postoperative VA data were included.

Visual loss was defined as a loss of ≥0.30 LogMAR (doubling or worse of the visual angle) between the preoperative and postoperative VA measurements. LogMAR VA is a continuous scale which allows arithmetic operations and parametric statistical methods to be employed in the analysis. Conversion between LogMAR and approximate Snellen scores, and their interpretations, are as follows:

Approximate Snellen to LogMAR Conversion
LogMAR
Snellen
VA Interpretation
-0.1
6/5
Excellent
0.0
6/6
Very Good
0.2
6/9
Good
0.3
6/12
Reasonably Good
0.5
6/18
Moderate
0.6
6/24
Moderate Sight Impairment
0.8
6/36
Sight Impairment
0.9
6/48
Sight Impairment
1.0
6/60
UK Severe Sight Impairment
1.1
5/60
UK Severe Sight Impairment
1.2
4/60
UK Severe Sight Impairment
3/60
WHO Severe Sight Impairment
2.1
Count Fingers (CF)
WHO Severe Sight Impairment
2.4
Hand Movements (HM)
WHO Severe Sight Impairment
2.7
Perception of Light (PL)
WHO Severe Sight Impairment
3.0
No Perception of Light (NPL)
WHO Severe Sight Impairment

## Appendix 4: Ocular Co-Pathology Changes

For the prospective data collection changes to the recording of ocular co-pathology were implemented. The intention is that in the future when sufficient operations have the individual components recorded separately this information could be investigated in the risk adjustment models. The new options were as follows;

- AMD could be specified as either 'dry AMD' or 'wet AMD' - No fundal view / vitreous opacities could be recorded separately as either 'no fundal view' or 
'vitreous opacities'
- Psuedoexfoliation / phacodenesis could be recorded separately as either 'psuedoexfoliation' or 
'phacodenesis'
- Uveitis / synaechiae could be recorded separately as either 'uveitis' or 'synaechiae' - When either 'macular hole' or 'epiretinal membrane peel' were recorded it was possible to record if 
with or without a prior pars plana vitrectomy (PPV). 
For the full results in this report these co-pathologies are not tabulated separately, but for interest overall figures for certain splits are summarised below. 

- Of the 11,398 operations recorded in eyes with AMD, 3,506 (30.8%) were recorded as 'dry' AMD, 
1,538 (13.5%) as 'wet' AMD and 6,354 (55.8%) as AMD without the specification of 'dry' or 'wet'.
- Of the 1,560 operations recorded in eyes with no fundal view / vitreous opacities, 812 (52.1%) were 
recorded as 'no fundal view', 66 (4.2%) as 'vitreous opacities' and 682 (43.7%) as combined.
- Of the 1,254 operations recorded in eyes with psuedoexfoliation / phacodenesis, 510 (40.7%) were 
recorded as 'psuedoexfoliation', 81 (6.5%) as 'phacodenesis' and 663 (52.9%) as combined.
- Of the 1,007 operations recorded in eyes with uveitis / synaechaie, 827 (82.1%) were recorded as 
'uveitis', none as 'synaechaie' and 180 (17.9%) as combined.
- Of the 510 operations recorded in eyes with macular hole, 168 (32.9%) were recorded with  
a previous PPV and of the 1,319 operations recorded in eyes with epiretinal membrane peel, 107 (8.1%) were recorded with a previous PPV.

## Appendix 5: Operative Procedures Combined With Phacoemulsification ± Iol

| Operative procedure                                          |   Frequency |
|--------------------------------------------------------------|-------------|
| Automated anterior vitrectomy                                |         995 |
| Limbal relaxing incisions / Opposite clear corneal incisions |         578 |
| Intravitreal injection                                       |         556 |
| Insertion of Iris hooks                                      |         520 |
| Insertion of pupil ring expander                             |         469 |
| Capsular tension ring                                        |         367 |
| Synaechiolysis                                               |         176 |
| Stretching of the Iris                                       |         158 |
| Injection of bleb (antimetabolite)                           |         151 |
| Pars plana vitrectomy                                        |         116 |
| Sphincterotomy                                               |          89 |
| Capsulectomy                                                 |          83 |
| Intraoperative phenylephrine                                 |          51 |
| Incision of Cornea                                           |          33 |
| Removal of retained lens fragments                           |          25 |
| Suture of Cornea                                             |          18 |
| Washout of anterior chamber                                  |          15 |
| IOL removal                                                  |          12 |
| Secondary IOL                                                |          11 |
| Examination under anaesthesia                                |          10 |
| Other specified operation on the Iris                        |           9 |
| Perfect capsule                                              |           7 |
| IOL exchange                                                 |           6 |
| Fragmatone lensectomy                                        |           5 |
| Removal Cornea sutures                                       |           5 |
| Sub-conjunctival injection                                   |           5 |
| Broad iridectomy                                             |           4 |
| I/C Miochol                                                  |           4 |

## Appendix 5: Operative Procedures Combined With Phacoemulsification ± Iol Continued

| Operative procedure                    |   Frequency |
|----------------------------------------|-------------|
| Injection into anterior chamber        |           4 |
| Removal of stent suture from Baerveldt |           4 |
| Implantation of intravitreal device    |           3 |
| Intravenous steroid injection          |           3 |
| Peripheral iridectomy                  |           3 |
| Healon GV                              |           2 |
| Surgical anterior capsulotomy          |           2 |
| Diathermy                              |           1 |
| IOL polish                             |           1 |
| Orbital floor injection                |           1 |
| Other specified excision of the Iris   |           1 |
| Reformation of anterior chamber of eye |           1 |
| Scleral-fixed IOL                      |           1 |

| Category                                                       |
|----------------------------------------------------------------|
| Aintree University Hospital NHS Foundation Trust               |
| Barking, Havering and Redbridge University Hospitals NHS Trust |
| Barnsley Hospital NHS Foundation Trust                         |
| Barts Health NHS Trust                                         |
| Bedford Hospital NHS Trust - Moorfields                        |
| Blackpool Teaching Hospitals NHS Foundation Trust              |
| Bradford Teaching Hospitals NHS Foundation Trust               |
| Calderdale and Huddersfield NHS Foundation Trust               |
| Cardiff and Vale University Health Board                       |
| Central Manchester University Hospitals NHS Foundation Trust   |
| Chesterfield Royal Hospital NHS Foundation Trust               |
| Croydon Health Services NHS Trust - Moorfields                 |
| East Sussex Healthcare NHS Trust*                              |
| Epsom and St Helier University Hospitals NHS Trust             |
| Signed up and                                                  |
| contributed data                                               |
| Frimley Health NHS Foundation Trust                            |
| Gloucestershire Hospitals NHS Foundation Trust                 |
| Hampshire Hospitals NHS Foundation Trust                       |
| Harrogate and District NHS Foundation Trust                    |
| Hinchingbrooke Health Care NHS Trust                           |
| Isle of Wight NHS Trust                                        |
| King's College Hospital NHS Foundation Trust                   |
| Leeds Teaching Hospitals NHS Trust                             |
| London North West Healthcare NHS Trust                         |
| Mid Cheshire Hospitals NHS Foundation Trust                    |
| Mid Essex Hospital Services NHS Trust                          |
| Mid Yorkshire Hospitals NHS Trust                              |
| Moorfields Eye Hospital NHS Foundation Trust                   |
| Norfolk and Norwich University Hospitals NHS Foundation Trust  |
| Northern Devon Healthcare NHS Trust                            |

| Category                                                              |
|-----------------------------------------------------------------------|
| Nottingham University Hospitals NHS Trust                             |
| Oxford University Hospitals NHS Trust                                 |
| Peterborough and Stamford Hospitals NHS Foundation Trust              |
| Plymouth Hospitals NHS Trust                                          |
| Royal Berkshire NHS Foundation Trust                                  |
| Royal Cornwall Hospitals NHS Trust                                    |
| Royal Free London NHS Foundation Trust                                |
| Royal United Hospital Bath NHS Trust                                  |
| Salisbury NHS Foundation Trust                                        |
| Sandwell and West Birmingham Hospitals NHS Trust                      |
| Sheffield Teaching Hospitals NHS Foundation Trust                     |
| Shrewsbury and Telford Hospital NHS Trust                             |
| South Tees Hospitals NHS Foundation Trust                             |
| South Warwickshire NHS Foundation Trust                               |
| Signed up and                                                         |
| contributed data                                                      |
| St Helens and Knowsley Hospitals NHS Trust                            |
| The Hillingdon Hospitals NHS Foundation Trust                         |
| The Newcastle Upon Tyne Hospitals NHS Foundation Trust                |
| The Royal Bournemouth and Christchurch Hospitals NHS Foundation Trust |
| University Hospital Southampton NHS Foundation Trust                  |
| University Hospitals Birmingham NHS Foundation Trust                  |
| University Hospitals Bristol NHS Foundation Trust                     |
| University Hospitals Coventry and Warwickshire NHS Trust              |
| University Hospitals of Morecambe Bay NHS Foundation Trust            |
| Warrington and Halton Hospitals NHS Foundation Trust                  |
| Wirral University Teaching Hospital NHS Foundation Trust              |
| Wrightington, Wigan and Leigh NHS Foundation Trust                    |
| Yeovil District Hospital NHS Foundation Trust                         |
| York Teaching Hospital NHS Foundation Trust                           |

| Category                                              |
|-------------------------------------------------------|
| Abertawe Bro Morgannwg University Health Board        |
| Ashford and St Peter's Hospitals NHS Foundation Trust |
| Bolton NHS Foundation Trust                           |
| Brighton and Sussex University Hospitals NHS Trust    |
| Buckinghamshire Healthcare NHS Trust                  |
| Burton Hospitals NHS Foundation Trust                 |
| Cambridge University Hospitals NHS Foundation Trust   |
| City Hospitals Sunderland NHS Foundation Trust        |
| Colchester Hospital University NHS Foundation Trust   |
| County Durham and Darlington NHS Foundation Trust     |
| Cwm Taf University Health Board                       |
| Dorset County Hospital NHS Foundation Trust           |
| East Cheshire NHS Trust                               |
| East Kent Hospitals University NHS Foundation Trust   |
| Signed up but                                         |
| not in time for                                       |
| submission of                                         |
| (sufficient)                                          |
| data for 1st                                          |
| prospective                                           |
| report                                                |
| East Lancashire Hospitals NHS Trust                   |
| George Eliot Hospital NHS Trust                       |
| Great Western Hospitals NHS Foundation Trust          |
| Guy's and St Thomas' NHS Foundation Trust             |
| Heart of England NHS Foundation Trust                 |
| Hull and East Yorkshire Hospitals NHS Trust           |
| Hywel Dda University Health Board                     |
| Imperial College Healthcare NHS Trust                 |
| James Paget University Hospitals NHS Foundation Trust |
| Kettering General Hospital NHS Foundation Trust       |
| Kingston Hospital NHS Trust                           |
| Luton and Dunstable Hospital NHS Foundation Trust     |
| Maidstone and Tunbridge Wells NHS Trust               |
| Milton Keynes Hospital NHS Foundation Trust           |
| North Cumbria University Hospitals NHS Trust          |

| Category                                                       |
|----------------------------------------------------------------|
| North Middlesex University Hospital NHS Trust                  |
| Northampton General Hospital NHS Trust                         |
| Northern Lincolnshire and Goole Hospitals NHS Foundation Trust |
| Pennine Acute Hospitals NHS Trust                              |
| Portsmouth Hospitals NHS Trust                                 |
| Powys Teaching Health Board                                    |
| Queen Victoria Hospital NHS Foundation Trust                   |
| Royal Devon and Exeter NHS Foundation Trust                    |
| Royal Liverpool and Broadgreen University Hospitals NHS Trust  |
| Royal Surrey County Hospital NHS Foundation Trust              |
| Sherwood Forest Hospitals NHS Foundation Trust                 |
| Southend University Hospital NHS Foundation Trust              |
| Southport and Ormskirk Hospital NHS Trust                      |
| Stockport NHS Foundation Trust                                 |
| Surrey and Sussex Healthcare NHS Trust                         |
| Taunton and Somerset NHS Foundation Trust                      |
| Signed up but                                                  |
| not in time for                                                |
| submission of                                                  |
| (sufficient)                                                   |
| data for 1st                                                   |
| prospective                                                    |
| report                                                         |
| The Dudley Group NHS Foundation Trust                          |
| The Ipswich Hospital NHS Trust                                 |
| The Princess Alexandra Hospital NHS Trust                      |
| The Queen Elizabeth Hospital King's Lynn NHS Foundation Trust  |
| The Rotherham NHS Foundation Trust                             |
| The Royal Wolverhampton NHS Trust                              |
| Torbay and South Devon NHS Foundation Trust                    |
| United Lincolnshire Hospitals NHS Trust                        |
| University Hospitals of Leicester NHS Trust                    |
| University Hospitals of North Midlands NHS Trust               |
| West Hertfordshire Hospitals NHS Trust                         |
| Wye Valley NHS Trust                                           |

| Category                                               |
|--------------------------------------------------------|
| Aneurin Bevan University Health Board                  |
| Betsi Cadwaladr University Health Board                |
| Chelsea and Westminster Hospital NHS Foundation Trust  |
| Countess of Chester Hospital NHS Foundation Trust      |
| Derby Teaching Hospitals NHS Foundation Trust          |
| Doncaster and Bassetlaw Hospitals NHS Foundation Trust |
| Yet to sign up                                         |
| or declined                                            |
| participation                                          |
| East and North Hertfordshire NHS Trust                 |
| Lancashire Teaching Hospitals NHS Foundation Trust     |
| West Suffolk NHS Foundation Trust                      |
| Worcestershire Acute Hospitals NHS Trust               |
| Western Sussex Hospitals NHS Trust                     |

* Data were excluded from reporting due to corrupt file

## Appendix 7: List Of Tables

| Table 1	                                                |                                                                                       | The number of eligible operations with the percentage performed by each grade 	                                                                                   |   16  |
|------------------------------------------------|---------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------|-------|
| of surgeon for the participating centre        |                                                                                       |                                                                                   |       |
| Table 2                                        |                                                                                       | Recorded Intra-operative complications for cataract operations for the first year |   28  |
| of the national audit by grade of surgeon      |                                                                                       |                                                                                   |       |
| Table 3                                        |                                                                                       | Postoperative VA by preoperative VA, ocular co-pathology and intra-operative      |   33  |
| complications                                  |                                                                                       |                                                                                   |       |
| Table 4                                        |                                                                                       | The percentage of eyes with preoperative VA, postoperative VA and change in       |   34  |
| VA data for participating centres in the audit |                                                                                       |                                                                                   |       |
| Table 5                                        | Posterior capsular rupture and VA Loss results for participating centres in the audit | 39                                                                                |       |

## Appendix 8: List Of Figures

| Figure 1	                                                                             |                                                                                    | The number of eligible operations supplied to the national cataract audit for 	                                                                                  |   20  |
|-----------------------------------------------------------------------------|------------------------------------------------------------------------------------|----------------------------------------------------------------------------------|-------|
| each contributing centre                                                    |                                                                                    |                                                                                  |       |
| Figure 2                                                                    |                                                                                    | The number of eligible operations supplied to the national cataract audit for    |   20  |
| each individual surgeon                                                     |                                                                                    |                                                                                  |       |
| Figure 3                                                                    |                                                                                    | Box and whisker plots of the national deciles of social deprivation for patients |   22  |
| undergoing cataract surgery during the audit period by participating centre |                                                                                    |                                                                                  |       |
| Figure 4                                                                    |                                                                                    | The percentage of cataract operations supplied to the audit with a missing       |   23  |
| preoperative VA by participating centre                                     |                                                                                    |                                                                                  |       |
| Figure 5                                                                    | Box and whisker plots of preoperative VA by participating centre                   | 24                                                                               |       |
| Figure 6                                                                    | Box and whisker plots of preoperative VA by national deciles of social deprivation | 24                                                                               |       |
| Figure 7                                                                    |                                                                                    | The percentage of cataract operations supplied to the audit with an ocular       |   25  |
| co-pathology by participating centre                                        |                                                                                    |                                                                                  |       |
| Figure 8                                                                    |                                                                                    | The percentage of cataract operations supplied to the audit with each            |   26  |
| individual ocular co-pathology                                              |                                                                                    |                                                                                  |       |
| Figure 9                                                                    |                                                                                    | The percentage of cataract operations supplied to the audit for each individual  |   27  |
| ocular co-pathology by grade of surgeon                                     |                                                                                    |                                                                                  |       |
| Figure 10                                                                   | The percentage of cataract operations supplied to the audit by postoperative       | 29                                                                               |       |
| complication status and participating centre                                |                                                                                    |                                                                                  |       |
| Figure 11                                                                   | The percentage of cataract operations supplied to the audit with each              | 30                                                                               |       |
| individual postoperative complication                                       |                                                                                    |                                                                                  |       |
| Figure 12                                                                   | The percentage of cataract operations supplied to the audit with a missing         | 31                                                                               |       |
| postoperative VA by participating centre                                    |                                                                                    |                                                                                  |       |
| Figure 13	 Box and whisker plots of postoperative VA by participating centre                                                                             | 31                                                                                 |                                                                                  |       |
| Figure 14	 Box and whisker plots of change in VA by participating centre                                                                             | 32                                                                                 |                                                                                  |       |
| Figure 15	 Unadjusted for case complexity PCR funnel plot for participating centres                                                                             | 38                                                                                 |                                                                                  |       |
| Figure 16	 Adjusted for case complexity PCR funnel plot for participating centres                                                                             | 38                                                                                 |                                                                                  |       |
| Figure 17	 Unadjusted for case complexity VA Loss funnel plot for participating centres                                                                             | 43                                                                                 |                                                                                  |       |
| Figure 18	 Adjusted for case complexity VA Loss funnel plot for participating centres                                                                             | 43                                                                                 |                                                                                  |       |

National Ophthalmology Database Audit The Royal College of Ophthalmologists 
18 Stephenson Way, London NW1 2HD
T. 020 7935 0702 
noa.project@rcophth.ac.uk nodaudit.org.uk