The Incidence of Venous Thromboembolism in Atopic Dermatitis: A Matched Cohort Analysis in UK Primary Care
Conditions: Venous Thromboembolism, Atopic Dermatitis, Pulmonary Embolism, Deep Vein Thrombosis, Allergic Rhinitis, Allergy to House Dust Mite, Allergy to Animal Dander, Food Allergy, Cows Milk Allergy
Sponsor: Momentum Data

The incidence of venous thromboembolism in atopic dermatitis: A 
matched cohort analysis in UK primary care: Statistical Analysis 
Plan and Protocol 
 
Document version 
1.1 
Date 
5 July 2021 
 
 

Contents 
List of abbreviations..................................................................................................................................................... 4 
1. Introduction ................................................................................................................................................................ 5 
1.1 Background ......................................................................................................................................................... 5 
Atopic dermatitis ................................................................................................................................................. 5 
Venous thromboembolism ............................................................................................................................... 5 
1.2. Purposes of analyses ....................................................................................................................................... 6 
2. Study objectives and endpoints .......................................................................................................................... 6 
2.1 Study objectives ................................................................................................................................................. 6 
2.2 Primary objective .............................................................................................................................................. 6 
2.3 Secondary objectives: ...................................................................................................................................... 6 
2.4 Primary endpoint .............................................................................................................................................. 6 
2.5 Secondary endpoints ....................................................................................................................................... 7 
2.6 Other exploratory analyses ........................................................................................................................... 7 
3 General Study Design and Plan ............................................................................................................................ 7 
3.1 Study Design........................................................................................................................................................ 7 
3.2 Data source and Read codes ......................................................................................................................... 7 
3.3 Data extraction ................................................................................................................................................... 7 
3.4 Inclusion-Exclusion Criteria and General Study Population ............................................................ 8 
Definition of atopic dermatitis ....................................................................................................................... 8 
Definition of AD cases (active atopic dermatitis) .................................................................................... 8 
Definition of atopic dermatitis severity ...................................................................................................... 9 
Definition of Allergic conditions .................................................................................................................... 9 
Definition of Anticoagulant prescriptions .................................................................................................. 9 
3.5 Baseline socio-economic characteristics: ................................................................................................ 9 
VTE history and established VTE risk factors .......................................................................................... 9 
4 Sample size calculations ....................................................................................................................................... 10 
5 Populations to be analysed .................................................................................................................................. 10 

5.1 
Inclusion Criteria ....................................................................................................................................... 10 
5.2 
Exclusion Criteria....................................................................................................................................... 10 
5.3 
Matching process ....................................................................................................................................... 10 
5.4 AD definition exploratory analyses .......................................................................................................... 11 
6 Statistical Analysis .................................................................................................................................................. 11 
6.1 Statistical principles ....................................................................................................................................... 11 
6.2 Primary Endpoint Analysis.......................................................................................................................... 11 
6.3 Secondary Endpoint Analysis ..................................................................................................................... 12 
6.4 Sensitivity analysis ......................................................................................................................................... 12 
6.5 Missing data ...................................................................................................................................................... 13 
7 Study Limitations .................................................................................................................................................... 13 
8 Statistical software .................................................................................................................................................. 13 
9 Ethics ............................................................................................................................................................................ 13 
References ...................................................................................................................................................................... 15 
Appendix 1 ..................................................................................................................................................................... 17 
Appendix 2 ..................................................................................................................................................................... 18 
Appendix 3 ..................................................................................................................................................................... 38 
Appendix 4 ..................................................................................................................................................................... 45 
 
 
 

List of abbreviations 
 
Abbreviation Full Form 
AD 
Atopic dermatitis 
ADEPT 
Anonymised Data Ethics Protocols and Transparency 
BMI 
Body mass index 
 
CI 
Confidence Interval 
CKD 
Chronic kidney disease 
COPD 
Chronic obstructive pulmonary disease 
DOAC 
Direct oral anticoagulant 
DVT 
Deep vein thrombosis 
GEP 
Good Epidemiological Practice 
GP 
General Practitioner 
  
GPP 
Good Pharmacoepidemiology Practices 
HR 
Hazard Ratio 
HRT 
Hormone replacement therapy 
IBD 
Inflammatory bowel disease 
IEA 
International Epidemiological Association 
IMD 
Index of multiple deprivation 
IQR 
Interquartile range 
ISPE 
International Society for Pharmacoepidemiology 
OPCRD 
Optimum Patient Care Research Database 
PE 
Pulmonary embolism 
RA 
Rheumatoid arthritis 
RECORD 
Reporting of studies conducted using observational routinely collected 
data 
SD 
Standard deviation 
TCI 
Topical calcineurin inhibitor 
VTE 
Venous thromboembolism 
 
 

1. Introduction 
1.1 Background 
Atopic dermatitis 
Atopic dermatitis (AD) is a chronic inflammatory skin condition that affects around 200 million 
people worldwide (1). The incidence of AD has risen significantly over recent decades, in 
particular in high income countries (2). It most commonly develops in the first year of life, 
although onset can occur at any age (3, 4). AD usually follows a chronic relapsing-remitting 
course, and maintaining disease control may require the use of ongoing treatment (5).  
 
Whilst many AD-affected children will have resolution or improvement by late childhood (3), a 
substantial proportion of people will have ongoing AD into adulthood, and flare ups can occur 
even after long periods of remission (4, 6). Itch, discomfort and visible skin lesions can result in 
disturbed sleep, social embarrassment and impaired quality of life (7). 
 
Given that the majority of AD patients are seen and treated principally in primary care in the UK, 
databases of electronic health records from general practitioner (GP) practices provide a rich 
data source from which epidemiological analyses can be derived (8).  
Venous thromboembolism 
Venous thromboembolism (VTE), which comprises pulmonary embolism (PE) and deep vein 
thrombosis (DVT), is relatively common, with an incidence in the general population of around 3 
cases per 1,000 patient years (9). It is associated with significant morbidity and mortality (10, 
11). 
 
VTE occurs due to a complex interplay of acquired or inherited thrombotic tendencies alongside 
various risk factors including active cancer, fractures, surgery, immobility, use of oral 
corticosteroids, superficial vein thrombosis, and in women, pregnancy and puerperium, oral 
contraception, and hormone therapy (12-15). In addition to these risk factors, conditions 
associated with chronic inflammation are increasingly being recognised as increasing the risk of 
VTE. Observational data demonstrate higher VTE rates in people with chronic inflammatory 
diseases including ulcerative colitis, Crohn’s disease, rheumatoid arthritis, psoriatic arthritis, and 
psoriasis compared to the general population (16-21). However, to our knowledge there have not 
been any large population-based studies assessing the incidence of VTE in people with AD 

compared to people without the condition.  Studies are also lacking as to whether known risk 
factors carry the same risk of VTE in people with and without AD. 
1.2. Purposes of analyses 
In this retrospective population-based study we will set out to establish the presence and 
magnitude of any excess risk of VTE in people with AD compared to a control population without 
AD. We will also explore potential heterogeneity in the risk of VTE across subgroups of people 
with AD defined by sociodemographic factors and established VTE risk factors which are 
prevalent in people with AD 
2. Study objectives and endpoints 
2.1 Study objectives 
The overall purpose of this study is to examine whether VTE is higher in people with AD 
compared and those without, and to explore the risk in particular subgroups of people with AD 
such as those with higher body mass index (BMI) or using oestrogen containing contraceptives. 
Such insights will be valuable for clinicians in advising patients with AD regarding VTE 
prevention and detection and when selecting AD treatments. 
2.2 Primary objective 
To describe the risk of VTE in people with AD compared to a matched control population. 
2.3 Secondary objectives: 
1) To describe the risk of PE and DVT individually in people with AD compared to a matched 
control population. 
 
2) To explore potential heterogeneity in the risk of VTE across subgroups of people with AD: by 
sex, age groups (18-45, 45-65, 65+), obesity, baseline use of oestrogen containing contraceptives 
in females, AD severity and history of allergic conditions. 
2.4 Primary endpoint 
The primary endpoint will be a diagnosis of VTE (a composite of PE or DVT) within 10 years 
starting from the index date. When both PE and DVT occur, the VTE diagnosis date will be the 
earliest of PE or DVT. 

2.5 Secondary endpoints 
1) Diagnosis of PE and diagnosis of DVT individually within 10 years starting from the index date. 
When both PE and DVT occur on the same event day this will be classified as a PE. Outcomes will 
be identified using previously validated, and subsequently updated, code lists.(22) 
 
2) Diagnosis of VTE (a composite of PE or DVT) within 10 years starting from the index date. 
 
2.6 Other exploratory analyses 
To cover the possibility of non-recorded VTE, we will analyse a composite of VTE diagnosis in 
people initiated on anticoagulant prescriptions without a recorded diagnosis of atrial fibrillation 
or prosthetic heart value. The potential VTE event date for those without a VTE diagnosis but 
started on an anticoagulant will be the date of initiation of the anticoagulant.  
 
3 General Study Design and Plan 
3.1 Study Design 
This is a non-interventional matched cohort study. 
3.2 Data source and Read codes 
This study will use routinely collected and collated data from the Optimum Patient Care Research 
Database (OPCRD).(23) This database incorporates pseudonymised primary care records from 
up to 700 GP practices distributed across England, Wales, Scotland and Northern Ireland. The 
current OPCRD cohort size is over 5 million actively registered people, and historic records 
available for 10.1 million people. The cohort dataset can be enhanced through direct-to-patient 
and direct-to-care provider questionnaires.  
3.3 Data extraction 
Individual patient data is anonymised at the point of data extraction. Queries will be executed to 
extract relevant data from the OPCRD using the Read code listed in Appendix 1. All data will 
remain in anonymised form and will be held on a secure server. The data will not be used for any 
purposes other than for the research which is described in the respective protocols and which 
has been approved by OPC. The sponsor, Pfizer Ltd, will not have access to the individual 
anonymised patient data. 

3.4 Inclusion-Exclusion Criteria and General Study Population 
Definition of atopic dermatitis 
AD will be identified using a combination of AD specific diagnosis Read and SNOMED codes, and 
two or more AD treatments prescribed on different dates. Diagnosis codes which are not specific 
for AD (e.g., hand dermatitis) are not included for AD case finding. The full list of diagnosis codes 
to be used is provided in Appendix 1. 
 
The treatments used to define AD will comprise; topical emollients, topical steroids, and topical 
calcineurin inhibitors. We will also make our AD case definition more stringent than that used by 
Abuabara et al. (24) by excluding people with conditions that may be misdiagnosed or miscoded 
as AD in primary care; these comprise psoriasis, contact dermatitis, photodermatitis, or 
ichthyosis. People with diagnosis codes for one or more of these conditions at any point in the 
clinical record will be excluded. 
Definition of AD cases (active atopic dermatitis) 
AD cases are defined as those people having active AD. Active AD will be identified as being 
present in those people prescribed one or more treatments for their AD in the last 365 days. The 
treatments used to define active AD comprise all those used to define AD with the addition of 
systemic 
immunomodulatory 
medications, 
including 
methotrexate, 
azathioprine, 
mycophenolate, cyclosporine, or AD specific biologic therapy (dupilumab being the only one 
licensed at during the study period). Systemic immunomodulatory medications will not be 
included in the AD case definition as this may lead to incorrect identification of AD cases in people 
with other autoimmune conditions for which these medications are used such as rheumatoid 
arthritis. This approach has been demonstrated to be in good agreement with physician 
confirmed active AD (24). 
 
All adults with an episode of active AD at any point between 1st Jan 2010 to 1st Jan 2015 will be 
included for analysis. People will be eligible for inclusion as an AD case if they have a minimum 
of five years of possible follow up, are aged 18 and over and have AD (using an approach derived 
from a validated AD case definition which is described in detail elsewhere(25)) which is active at 
some point during the observation period. 
 
The study period will be a ten-year period from 1st Jan 2010 to 1st Jan 2020. Individuals must 
enter the study on or before 1st Jan 2015 in order to have a possible minimum follow up duration 

of five years. The start of follow up (index date) for each AD case will be the start of their period 
of active AD. Their follow-up will end at either the earliest of the following: date of deregistration, 
date of reaching age 95, date of death, or date of the end of the study period (1st Jan 2020). 
Definition of atopic dermatitis severity 
AD severity will be defined using the approach used by Silverwood et al. in their study of 
cardiovascular outcomes in AD:(26) AD will be considered moderate at the prescription of a 
second potent topical corticosteroid treatment within one year or a first topical calcineurin 
inhibitor (TCI). AD will be considered severe at the first of a systemic immunosuppressant 
treatment (ciclosporin, azathioprine, mycophenolate, methotrexate, and biologics), phototherapy, 
or a dermatology referral. 
Definition of Allergic conditions 
Allergic conditions will comprise common allergies; allergic rhinitis, allergy to dust mites or 
animal dander, and food allergies e.g., nut, fruit, shellfish, eggs and cows' milk allergies. 
Medication and other allergies will not be included. 
Definition of Anticoagulant prescriptions 
Anticoagulant prescriptions will comprise vitamin K antagonists (warfarin), low molecular 
weight heparins, and direct-acting oral anticoagulants. 
3.5 Baseline socio-economic characteristics: 
Age, sex, ethnic group and socioeconomic status will comprise the sociodemographic exposures 
of interest. Ethnicity will be extracted from the primary care record and grouped into major UK 
ethnic groups; White, Black, Asian, Mixed, and Others (27). Socioeconomic status will be defined 
using index of multiple deprivation (IMD), the official national measure of socioeconomic status 
in the UK (28). 
VTE history and established VTE risk factors 
Baseline history of VTE will be extracted from the primary care record using the same definition 
as for the primary VTE endpoint. VTE risk factors have be selected based on existing literature 
demonstrating an established association with VTE (12, 19), clinical expertise, or their inclusion 
in the QThrombosis tool (29). These will comprise of age, BMI, smoking and alcohol use, evidence 
of reduced mobility, known thrombophilia, recent hospital admission (prior six months), and the 
presence of comorbidities; varicose vein surgery, chronic kidney disease (CKD) stages 4 or 5, 

malignancy, heart failure, chronic obstructive pulmonary disease (COPD), inflammatory bowel 
disease (IBD) and rheumatoid arthritis (RA). 
 
4 Sample size calculations 
No previous studies have examined VTE risk in people with AD to provide an estimation of effect 
size to inform our sample size calculation. Assuming 80% power, a 1:1 ratio of AD cases to 
controls, and an overall probability of VTE over the study period of 1% (a conservative estimate 
based on a previous analysis of VTE incidence in the general population (17), a sample size of 
33,899 will be required to detect a minimum clinically relevant effect size of a 20% increased risk 
of VTE in the AD cohort compared to population controls. We anticipate that in excess of 50,000 
people in our study cohort will have an episode of active AD during the study period and so be 
defined as AD cases, these will be 1:1 matched to population controls providing a study cohort 
well in excess of this required sample size. 
5 Populations to be analysed 
5.1 Inclusion Criteria 
All adult people (aged ≥ 18) registered with GP practices contributing data to OPCRD between 
January 1, 2010 and January 1, 2020, are eligible for inclusion in the study. 
5.2 Exclusion Criteria 
People with less than 5 years potential follow up. 
People with AD that was not active during the study period. 
People without AD but diagnosed with other skin conditions (psoriasis, contact dermatitis, 
photodermatitis, or ichthyosis). 
5.3 Matching process 
Each adult with active AD will be 1:1 matched at their index date using, nearest neighbour 
matching (30) to another person without AD (people never diagnosed either with AD or any 
exclusion skin condition (psoriasis, contact dermatitis, photodermatitis, or ichthyosis, Appendix 
2) at the date of matching). Matching variables will comprise age, sex, duration of practice 
registration and within primary care practice where numbers allow. After matching, the index 
date for each control will be set at the index date of their matched counterpart. 

5.4 AD definition exploratory analyses 
We will explore other recorded dermatology conditions to ensure that the AD case definition is 
correctly identifying people with AD; this analysis will be performed in practices using the Read 
version 2 coding system where is it possible to use search terms M1% and M2% (where % is a 
wild card) to extract all non-infectious dermatology diagnoses. 
6 Statistical Analysis 
6.1 Statistical principles 
The mean, standard deviation (sd) and any other statistical measures, will be reported to one 
decimal place. Continuous data will be summarised in the form of means, sd, median, 
interquartile range (IQR) and range as appropriate. Categorical data will be summarised using 
frequencies and proportions. Chi-squared and t-tests will be performed to compare the 
frequency of dichotomous variables and the values of continuous variables where relevant. 95% 
CIs will be reported for main effect sizes.  Statistical significance will be assessed using p<0.05. 
Actual p-values will be reported except for p-values less than 3 decimal places which will be 
reported as “<0.001”. P-values >0.1 will be reported to one decimal place, p-values between 0.01 
and 0.1 will be reported to 2 decimal places, and p-values between 0.001 and 0.01 will be 
reported to three decimal places. 
 
The assessment of any associations with baseline characteristics and the primary endpoint will 
be assessed using Cox proportional hazards models. A standard set of features will be used in all 
multivariable models as listed in section 6.2. 
 
Assumptions of statistical approaches will be assessed, and transformations used if necessary 
(although it is not anticipated that the data will violate model assumptions). 
 
6.2 Primary Endpoint Analysis 
Risk of new onset VTE will be assessed prospectively in AD cases and matched controls from the 
index date. The clinical codes used to define the VTE end points are listed in Appendix 3. Risk of 
developing each VTE condition within 10 years will then be examined using time to event analysis. 
Initially, unadjusted Cox proportional hazards models, stratified by matched set (AD cases versus 
matched controls), will be used to provide overall hazard ratios (HRs) as summary estimates for 
the association of the presence of active AD with the time to each VTE condition. Models will be 

adjusted for baseline sociodemographic and clinical features, and VTE risk factors in 
multivariable analysis. These comprise of age, ethnicity, SES, number of primary care visits in the 
preceding year. BMI, smoking and alcohol use, evidence of reduced mobility, known 
thrombophilia, recent hospital admission (prior six months), and the presence of comorbidities; 
varicose vein surgery, CKD stages 4 or 5, malignancy, heart failure, COPD, IBD and RA. We will 
also control for active prescribing at baseline of the following medications: oral corticosteroids 
(which can be used in AD treatment), hormone therapy (oestrogen containing oral hormonal 
contraceptives, and hormone replacement therapy [HRT]), antiplatelet agents (aspirin or 
adenosine diphosphate receptor inhibitors), warfarin, and direct oral anticoagulants (DOACs). 
Hormonal contraceptives comprised only combined oestrogen and progestogen preparations; 
progesterone only contraceptives will not be included as these preparations are not associated 
with VTE (31). HRT comprises of systemic oestrogen only preparations. Active prescribing at 
baseline will be defined as an issued prescription in the 3 months preceding and/or 1 month 
after the person’s start date. A full list of the study variables in included in Appendix 4. 
 
6.3 Secondary Endpoint Analysis 
The secondary endpoint analysis will be assessed using the same statistical principles as the 
primary endpoint. Only risk of the composite VTE endpoint will be applied for the subgroup 
analysis. 
6.4 Sensitivity analysis 
We will repeat the primary analysis excluding AD cases and controls (and their corresponding 
matched pair) with a history of VTE at cohort entry. 
 
To evaluate the magnitude of potential bias from including as controls people who are registered 
with GP practices but who do not attend their practice, we will repeat the primary outcome 
analysis including only controls with a least one primary care consultation in the year before 
index date (NB this is a likely over-adjustment as the remaining controls with be less a healthy 
group than the general population). 
 
To mitigate the possibility of misclassification of AD severity caused by the use of systemic 
treatments for other inflammatory conditions we will repeat the primary analysis and AD 
severity subgroup analyses in a subgroup of people without the following conditions; IBD (both 
ulcerative colitis and Crohn’s disease) and RA. 

 
6.5 Missing data 
This study will use the missing indicator variable method as missing data are considered likely 
not to be missing at random, meaning multiple imputation approaches will lack validity. 
 
Patients will need to be excluded from analyses based on a matched design if they have 
incomplete data in the fields (age, sex) required to run the matching process. In similar studies, 
the exclusion rate due to incomplete data has been low (32, 33). 
7 Study Limitations 
Although the data is derived from a validated and nationally representative sample of the UK, 
results should not be extrapolated to dissimilar populations. Important limitations of the study 
include the reliance on comprehensive code lists to identify any given baseline or outcome 
variable. This limitation is common to all studies using routinely recorded data and will be 
mitigated through the use of a validated approach for defining baseline and outcome parameters. 
(34). 
 
Limitations exist in the amount of clinical detail presently recorded in routine primary care 
electronic health records. Routine primary care databases offer the benefit of large cohorts at the 
expense of granularity; a limitation that is universal in epidemiological studies of this type. Some 
analyses will be restricted to people in whom complete information is available which may 
introduce selection bias as a result. Finally, the data presented will be observational in nature 
and although attempts will be made to reduce confounding by statistical adjustment where 
relevant, it is not possible to exclude the possibility of residual confounding as part of the 
explanation for any findings. 
8 Statistical software 
All statistical analyses will be performed using R software version 3.4.1. 
 
9 Ethics 
This study requires approval by the Anonymised Data Ethics Protocols and Transparency 
(ADEPT) Committee. It has been uploaded to ClinicalTrials.gov. 
 

The study will be conducted in accordance with legal and regulatory requirements, as well as 
with scientific purpose, value, and rigor and follow generally accepted research practices 
described in Guidelines for Good Pharmacoepidemiology Practices (GPP) issued by the 
International Society for Pharmacoepidemiology (ISPE), and Good Epidemiological Practice (GEP) 
guidelines issued by the International Epidemiological Association (IEA). Study reporting will be 
conducted in accordance with the RECORD (Reporting of studies conducted using observational 
routinely collected data) guidelines (35). 
 

References 
1. 
Langan SM, Irvine AD, Weidinger S. Atopic dermatitis. The Lancet. 2020;396(10247):345-
60. 
2. 
Nutten S. Atopic Dermatitis: Global epidemiology and risk factors. Annal Nutri Metab. 
2015;66:8-16. 
3. 
Illi S, von Mutius E, Lau S, Nickel R, Gruber C, Niggemann B, et al. The natural course of 
atopic dermatitis from birth to age 7 years and the association with asthma. The Journal of allergy 
and clinical immunology. 2004;113(5):925-31. 
4. 
Garmhausen D, Hagemann T, Bieber T, Dimitriou I, Fimmers R, Diepgen T, et al. 
Characterization of different courses of atopic dermatitis in adolescent and adult patients. Allergy. 
2013;68(4):498-506. 
5. 
Weidinger 
S, 
Novak 
N. 
Atopic 
dermatitis. 
Lancet 
(London, 
England). 
2016;387(10023):1109-22. 
6. 
Peters AS, Kellberger J, Vogelberg C, Dressel H, Windstetter D, Weinmayr G, et al. 
Prediction of the incidence, recurrence, and persistence of atopic dermatitis in adolescence: a 
prospective cohort study. The Journal of allergy and clinical immunology. 2010;126(3):590-5.e1-
3. 
7. 
Drucker AM, Wang AR, Li WQ, Sevetson E, Block JK, Qureshi AA. The Burden of Atopic 
Dermatitis: Summary of a Report for the National Eczema Association. J Invest Dermatol. 
2017;137(1):26-30. 
8. 
Emerson RM, Williams HC, Allen BR. Severity distribution of atopic dermatitis in the 
community and its relationship to secondary referral. The British journal of dermatology. 
1998;139(1):73-6. 
9. 
Walker AJ, Card TR, West J, Crooks C, Grainge MJ. Incidence of venous thromboembolism 
in patients with cancer - a cohort study using linked United Kingdom databases. European 
journal of cancer (Oxford, England : 1990). 2013;49(6):1404-13. 
10. 
Cohen AT, Agnelli G, Anderson FA, Arcelus JI, Bergqvist D, Brecht JG, et al. Venous 
thromboembolism (VTE) in Europe. The number of VTE events and associated morbidity and 
mortality. Thrombosis and haemostasis. 2007;98(4):756-64. 
11. 
Winter 
MP, 
Schernthaner 
GH, 
Lang 
IM. 
Chronic 
complications 
of 
venous 
thromboembolism. Journal of thrombosis and haemostasis : JTH. 2017;15(8):1531-40. 
12. 
Huerta C, Johansson S, Wallander M, Garcí a Rodrí guez LA. Risk factors and short-term 
mortality of venous thromboembolism diagnosed in the primary care setting in the united 
kingdom. Archives of Internal Medicine. 2007;167(9):935-43. 
13. 
Dregan A, Charlton J, Chowienczyk P, Gulliford MC. Chronic Inflammatory Disorders and 
Risk of Type 2 Diabetes Mellitus, Coronary Heart Disease, and Stroke. Circulation. 
2014;130(10):837-44. 
14. 
Zakai NA, Wright J, Cushman M. Risk factors for venous thrombosis in medical inpatients: 
validation of a thrombosis risk score. Journal of thrombosis and haemostasis : JTH. 
2004;2(12):2156-61. 
15. 
Heit JA. Epidemiology of venous thromboembolism. Nat Rev Cardiol. 2015;12(8):464-74. 
16. 
Branchford BR, Carpenter SL. The Role of Inflammation in Venous Thromboembolism. 
Frontiers in pediatrics. 2018;6:142-. 
17. 
Galloway J, Barrett K, Irving P, Khavandi K, Nijher M, Nicholson R, et al. Risk of venous 
thromboembolism in immune-mediated inflammatory diseases: a UK matched cohort study. 
RMD Open. 2020;6(3). 
18. 
Choi HK, Rho Y-H, Zhu Y, Cea-Soriano L, Avin a-Zubieta JA, Zhang Y. The risk of pulmonary 
embolism and deep vein thrombosis in rheumatoid arthritis: a UK population-based outpatient 
cohort study. Annals of the Rheumatic Diseases. 2013;72(7):1182-7. 

19. 
Ogdie A, Kay McGill N, Shin DB, Takeshita J, Jon Love T, Noe MH, et al. Risk of venous 
thromboembolism in patients with psoriatic arthritis, psoriasis and rheumatoid arthritis: a 
general population-based cohort study. European Heart Journal. 2018;39(39):3608-14. 
20. 
Grainge MJ, West J, Card TR. Venous thromboembolism during active disease and 
remission in inflammatory bowel disease: a cohort study. The Lancet. 2010;375(9715):657-63. 
21. 
Murthy SK, Nguyen GC. Venous Thromboembolism in Inflammatory Bowel Disease: An 
Epidemiological Review. The American Journal Of Gastroenterology. 2011;106:713. 
22. 
Lawrenson R, Todd JC, Leydon GM, Williams TJ, Farmer RD. Validation of the diagnosis of 
venous thromboembolism in general practice database studies. British journal of clinical 
pharmacology. 2000;49(6):591-6. 
23. 
OPCRD. OPCRD The Optimum Patient Care Research Database 2016 [Available from: 
http://optimumpatientcare.org/opcrd/. 
24. 
Abuabara K, Magyari AM, Hoffstad O, Jabbar-Lopez ZK, Smeeth L, Williams HC, et al. 
Development and Validation of an Algorithm to Accurately Identify Atopic Eczema Patients in 
Primary Care Electronic Health Records from the UK. J Invest Dermatol. 2017;137(8):1655-62. 
25. 
de Lusignan S, Alexander H, Broderick C, Dennis J, McGovern A, Feeney C, et al. 
Epidemiology and management of atopic dermatitis in England: an observational cohort study 
protocol. BMJ Open. 2020;10(9):e037518. 
26. 
Silverwood RJ, Forbes HJ, Abuabara K, Ascott A, Schmidt M, Schmidt SAJ, et al. Severe and 
predominantly active atopic eczema in adulthood and long term risk of cardiovascular disease: 
population based cohort study. BMJ (Clinical research ed). 2018;361:k1786. 
27. 
Tippu Z, Correa A, Liyanage H, Burleigh D, McGovern A, Van Vlymen J, et al. Ethnicity 
Recording in Primary Care Computerised Medical Record Systems: An Ontological Approach. J 
Innov Health Inform. 2017;23(4):920. 
28. 
Department for Communities and Local Government. The English Indices of Deprivation. 
2015. 
 
[Internet; 
cited 
2019 
Jun 
16]. 
Available 
from: 
https://www.gov.uk/government/statistics/english-indices-of-deprivation-2015. 
29. 
Hippisley-Cox J, Coupland C. Development and validation of risk prediction algorithm 
(QThrombosis) to estimate future risk of venous thromboembolism: prospective cohort study. 
BMJ. 2011;343:d4656. 
30. 
Wang SV, Schneeweiss S, Rassen JA. Optimal matching ratios in drug safety surveillance. 
Epidemiology. 2014;25(5):772-3. 
31. 
Mantha S, Karp R, Raghavan V, Terrin N, Bauer KA, Zwicker JI. Assessing the risk of venous 
thromboembolic events in women taking progestin-only contraception: a meta-analysis. BMJ. 
2012;345(aug07 2):e4944-e. 
32. 
Kumar S, de Lusignan S, McGovern A, Correa A, Hriskova M, Gatenby P, et al. Ischaemic 
stroke, haemorrhage, and mortality in older patients with chronic kidney disease newly started 
on anticoagulation for atrial fibrillation: a population based study from UK primary care. Bmj. 
2018;360:k342. 
33. 
Rayner LH, Mcgovern A, Sherlock J, Gatenby P, Correa A, Creagh-Brown B, et al. The impact 
of therapy on the risk of asthma in type 2 diabetes. Clin Respir J. 2019;13(5):299-305. 
34. 
de Lusignan S, Liaw ST, Michalakidis G, Jones S. Defining datasets and creating data 
dictionaries for quality improvement and research in chronic disease using routinely collected 
data: an ontology-driven approach. Informatics in primary care. 2011;19(3):127-34. 
35. 
Benchimol EI, Smeeth L, Guttmann A, Harron K, Moher D, Petersen I, et al. The REporting 
of studies Conducted using Observational Routinely-collected health Data (RECORD) statement. 
PLoS Med. 2015;12(10):e1001885. 
 
 
 

Appendix 1 
Diagnosis codes which will be used as part of an algorithm to identify people with atopic 
dermatitis. The included codes lists cover the three coding systems currently in using in UK 
primary care; Read V2, Read CTV3, SNOMED CT. 
 
Read V2 Code 
Code description 
M12z1 
Eczema NOS 
M111. 
Atopic dermatitis/eczema 
M112. 
Infantile eczema 
M113. 
Flexural eczema 
M114. 
Allergic (intrinsic) eczema 
Read CTV3 Code 
Description 
X505K 
Eczema 
X505M 
Constitutional eczema 
M111. 
Atopic dermatitis 
M113. 
Flexural atopic dermatitis 
M112. 
Infantile eczema 
SNOMED CT ID 
Description 
24079001 
Atopic dermatitis 
402196005 
Childhood atopic dermatitis (disorder) 
402195009 
Infantile atopic dermatitis (disorder) 
402183009 
Flexural atopic dermatitis 
402197001 
Adult atopic dermatitis 
90823000 
Infantile eczema 
43116000 
Eczema 
57092006 
Flexural eczema 
 
 

Appendix 2 
Diagnosis codes which will be used to identify AD case exclusion skin conditions. 
 
Psoriasis 
Read V2 Code 
Code description 
M16.. 
Psoriasis and similar disorders 
M161. 
Other psoriasis 
M1610 
Psoriasis unspecified 
M1611 
Psoriasis annularis 
M1612 
Psoriasis circinata 
M1613 
Psoriasis diffusa 
M1614 
Psoriasis discoidea 
M1615 
Psoriasis geographica 
M1616 
Guttate psoriasis 
M1617 
Psoriasis gyrata 
M1618 
Psoriasis inveterata 
M1619 
Psoriasis ostracea 
M161A 
Psoriasis palmaris 
M161B 
Psoriasis plantaris 
M161C 
Psoriasis punctata 
M161D 
Pustular psoriasis 
M161E 
Psoriasis universalis 
M161F 
Psoriasis vulgaris 
M161G 
Acrodermatitis continua 
M161H 
Erythrodermic psoriasis 
M161J 
Flexural psoriasis 
M161z 
Psoriasis NOS 
M166. 
Palmoplantar pustular psoriasis 
M16y. 
Other psoriasis and similar disorders 
M16y0 
Scalp psoriasis 
M16z. 
Psoriasis and similar disorders NOS 
Myu30 
[X]Other psoriasis 
N0452 
Juvenile arthritis in psoriasis 
Read CTV3 Code 
Description 
X506Y 
Psoriasis 
XaYOx 
Pustular psoriasis 
X506p 
Generalised pustular psoriasis 
X506q 
Acute generalised pustular psoriasis 
X506r 
Generalised pustular psoriasis of pregnancy 
X506s 
Pustular psoriasis in children 
X506t 
Juvenile pustular psoriasis 
X506u 
Infantile pustular psoriasis 
X506l 
Localised pustular psoriasis 
X506m 
Palmoplantar pustular psoriasis 
M07y0 
Acute palmoplantar pustular psoriasis 
M161A 
Psoriasis palmaris 

M161B 
Psoriasis plantaris 
X506o 
Lapiere type of psoriasis 
X506v 
Circinate and annular pustular psoriasis 
M1611 
Psoriasis annularis 
M1612 
Psoriasis circinata 
M1614 
Plaque psoriasis 
XaNXa 
Chronic large plaque psoriasis 
M1616 
Guttate psoriasis 
X506Z 
Flexural psoriasis 
X506a 
Unstable psoriasis 
X506b 
Erythrodermic psoriasis 
X506i 
Scalp psoriasis 
M161. 
Other psoriasis 
M1610 
Psoriasis unspecified 
M1613 
Psoriasis diffusa 
M1615 
Psoriasis geographica 
M1617 
Psoriasis gyrata 
M1618 
Psoriasis inveterata 
M161C 
Psoriasis punctata 
M161E 
Psoriasis universalis 
XaNXt 
Psoriasis vulgaris 
M161z 
Psoriasis NOS 
Myu30 
[X]Other psoriasis 
SNOMED CT ID 
Description 
9014002 
Psoriasis (disorder)  
402325007 
Drug-exacerbated psoriasis (disorder)  
402329001 
Early onset psoriasis type 1 (disorder)  
402332003 
Onset of psoriasis in adolescence (10-20 years) (disorder)  
402331005 
Onset of psoriasis in childhood (1-10 years) (disorder)  
402333008 
Onset of psoriasis in early adulthood (20-40 years) (disorder)  
402330006 
Onset of psoriasis in infancy (<1 year) (disorder)  
238603004 
Eczematized psoriasis (disorder)  
200977004 
Erythrodermic psoriasis (disorder)  
402335001 
Familial psoriasis (disorder)  
402336000 
Familial psoriasis with affected first degree relative (disorder)  
402337009 
Familial psoriasis without affected first degree relative (disorder)  
719810000 
X-linked intellectual disability with seizure and psoriasis syndrome (disorder)  
238600001 
Flexural psoriasis (disorder)  
402317005 
Generalized psoriasis (disorder)  
37042000 
Guttate psoriasis (disorder)  
402312004 
Acute guttate psoriasis (disorder)  
402313009 
Guttate flare of psoriasis with preexisting plaques (disorder)  
402322005 
Hypertrophic palmar psoriasis (disorder)  
402323000 
Hypertrophic palmoplantar psoriasis (disorder)  
238609000 
K”bner psoriasis (disorder)  
402334002 
Late onset psoriasis type 2 (disorder)  
402321003 
Non-pustular psoriasis of hands (disorder)  

402324006 
Non-pustular psoriasis of hands and feet (disorder)  
402318000 
Photoaggravated psoriasis (disorder)  
200965009 
Plaque psoriasis (disorder)  
402311006 
Actively extending plaque psoriasis (disorder)  
402308005 
Chronic small plaque psoriasis (disorder)  
402309002 
Chronic guttate pattern psoriasis (disorder)  
402307000 
Chronic large plaque psoriasis (disorder)  
402310007 
Chronic stable plaque psoriasis (disorder)  
200962007 
Psoriasis annularis (disorder)  
200963002 
Psoriasis circinata (disorder)  
200964008 
Psoriasis diffusa (disorder)  
200966005 
Psoriasis geographica (disorder)  
200967001 
Psoriasis gyrata (disorder)  
200968006 
Psoriasis inveterata (disorder)  
721538000 
Psoriasis of anogenital region (disorder)  
402315002 
Psoriasis of penis (disorder)  
402316001 
Psoriasis of perianal skin (disorder)  
402314003 
Psoriasis of vulva (disorder)  
402320002 
Psoriasis of face (disorder)  
238604005 
Psoriasis of nail (disorder)  
238605006 
Psoriatic nail dystrophy (disorder)  
238606007 
Psoriatic nail pitting (disorder)  
402319008 
Psoriasis of scalp margin (disorder)  
200971003 
Psoriasis plantaris (disorder)  
200972005 
Psoriasis punctata (disorder)  
200974006 
Psoriasis universalis (disorder)  
200975007 
Psoriasis vulgaris (disorder)  
33339001 
Psoriasis with arthropathy (disorder)  
238602009 
Psoriasis-eczema overlap condition (disorder)  
200973000 
Pustular psoriasis (disorder)  
402327004 
Acute generalized pustular flare of preexisting plaque psoriasis (disorder)  
238617008 
Circinate and annular pustular psoriasis (disorder)  
238612002 
Generalized pustular psoriasis (disorder)  
402326008 
Acute generalized pustular psoriasis de novo (disorder)  
238613007 
Generalized pustular psoriasis of pregnancy (disorder)  
238616004 
Infantile pustular psoriasis (disorder)  
238615000 
Juvenile pustular psoriasis (disorder)  
28840001 
Generalized pustular psoriasis, exanthematous type (disorder)  
238611009 
Lapiere type of psoriasis (disorder)  
81271001 
Localized pustular psoriasis (disorder)  
83839005 
Acrodermatitis continua of Hallopeau (disorder)      
784328000 
Pustular psoriasis of palm of hand (disorder)  
27520001 
Pustular psoriasis of palms and soles (disorder)  
239098009 
Acropustulosis of infancy (disorder)    
784327005 
Pustular psoriasis of sole of foot (disorder)  
200969003 
Rupioid psoriasis (disorder)  
238608008 
Scalp psoriasis (disorder)  

25847004 
Seborrheic psoriasis (disorder)  
238601002 
Unstable psoriasis (disorder)  
161562002 
History of psoriasis (situation)  
11188005 
Psoriasiform napkin eruption (disorder)  
400069004 
Nevoid psoriasis (disorder)  
866341000000101 
Psoriasis area and severity index score (observable entity)  
239803008 
Juvenile psoriatic arthritis with psoriasis (disorder) 
Contact Dermatitis 
Read V2 Code 
Code description 
Myu21 
[X]Allergic contact dermatitis due to other chemical products 
Myu23 
[X]Allergic contact dermatitis due to other agents 
Myu24 
[X]Irritant contact dermatitis due to other chemical products 
Myu25 
[X]Irritant contact dermatitis due to other agents 
Myu26 
[X]Unspecified contact dermatitis due to other chemical products 
Myu27 
[X]Unspecified contact dermatitis due to other agents 
M12.. 
Contact dermatitis and other eczemas 
M120. 
Contact dermatitis due to detergents 
M121. 
Contact dermatitis due to oils and greases 
M122. 
Contact dermatitis due to solvents 
M1220 
Contact dermatitis due to chlorocompound 
M1221 
Contact dermatitis due to cyclohexane 
M1222 
Contact dermatitis due to ester 
M1223 
Contact dermatitis due to glycol 
M1224 
Contact dermatitis due to hydrocarbon 
M1225 
Contact dermatitis due to ketone 
M122z 
Contact dermatitis due to solvent NOS 
M123. 
Contact dermatitis due to drugs and medicaments 
M1230 
Contact dermatitis due to arnica 
M1231 
Contact dermatitis due to fungicides 
M1232 
Contact dermatitis due to iodine 
M1233 
Contact dermatitis due to keratolytics 
M1234 
Contact dermatitis due to mercurials 
M1235 
Contact dermatitis due to neomycin 
M1236 
Contact dermatitis due to pediculocides 
M1237 
Contact dermatitis due to phenols 
M1238 
Contact dermatitis due to scabicides 
M123z 
Contact dermatitis due to medicament NOS 
M124. 
Contact dermatitis due to other chemical products 
M1240 
Contact dermatitis due to acids 
M1241 
Contact dermatitis due to adhesive plaster 
M1242 
Contact dermatitis due to alkalis 
M1243 
Contact dermatitis due to caustics 
M1244 
Contact dermatitis due to dichromate 
M1245 
Contact dermatitis due to insecticide 
M1246 
Contact dermatitis due to nylon 
M1247 
Contact dermatitis due to plastic 
M1248 
Contact dermatitis due to rubber 

M124z 
Contact dermatitis: other chemicals NOS 
M125. 
Contact dermatitis due to food in contact with skin 
M1250 
Contact dermatitis due to cereals 
M1251 
Contact dermatitis due to fish 
M1252 
Contact dermatitis due to flour 
M1253 
Contact dermatitis due to fruit 
M1254 
Contact dermatitis due to meat 
M1255 
Contact dermatitis due to milk 
M125z 
Contact dermatitis due to food NOS 
M126. 
Contact dermatitis due to plants 
M1260 
Contact dermatitis due to lacquer tree 
M1261 
Contact dermatitis due to poison-ivy 
M1262 
Contact dermatitis due to poison-oak 
M1263 
Contact dermatitis due to poison-sumac 
M1264 
Contact dermatitis due to poison-vine 
M1265 
Contact dermatitis due to primrose 
M1266 
Contact dermatitis due to ragweed 
M126z 
Contact dermatitis due to plants NOS 
M128. 
Allergic contact dermatitis 
M1280 
Allergic contact dermatitis due to adhesives 
M1281 
Allergic contact dermatitis due to cosmetics 
M1282 
Allergic contact dermatitis due to drugs in contact with the skin 
M1283 
Allergic contact dermatitis due to dyes 
M1284 
Allergic contact dermatitis due to other chemical products 
M1285 
Allergic contact dermatitis due to food in contact with the skin 
M1286 
Allergic contact dermatitis due to plants, except food 
M129. 
Irritant contact dermatitis 
M1290 
Irritant contact dermatitis due to cosmetics 
M1291 
Irritant contact dermatitis due to drugs in contact with the skin 
M1292 
Irritant contact dermatitis due to other chemical products 
M1293 
Irritant contact dermatitis due to food in contact with the skin 
M1294 
Irritant contact dermatitis due to plants, except food 
M12y. 
Contact dermatitis due to other specified agents 
M12y0 
Contact dermatitis due to cosmetics 
M12y1 
Contact dermatitis due to cold weather 
M12y2 
Contact dermatitis due to dyes 
M12y3 
Contact dermatitis due to furs 
M12y4 
Contact dermatitis due to hot weather 
M12y5 
Contact dermatitis due to infra-red rays 
M12y6 
Contact dermatitis due to jewellery 
M12y7 
Contact dermatitis due to light (excluding sunlight) 
M12y8 
Contact dermatitis due to metals 
M12y9 
Contact dermatitis due to preservatives 
M12yA 
Contact dermatitis due to radiation NOS 
M12yB 
Contact dermatitis due to ultra-violet rays (excluding sunlight) 
M12yC 
Contact dermatitis due to x-rays 
M12yD 
Contact dermatitis due to casting materials 

M12yz 
Contact dermatitis: specified agent NOS 
M12z. 
Contact dermatitis NOS 
M12zz 
Contact dermatitis NOS 
Read CTV3 Code 
Description 
Xa9CV 
Contact dermatitis 
X505x 
Allergic contact dermatitis 
X505y 
Nickel sensitivity 
X505z 
Implant allergic nickel contact dermatitis 
X5060 
Ingested allergen contact dermatitis 
Xa0Wg 
Baboon syndrome 
X5061 
Photoallergic contact dermatitis 
M1280 
Allergic contact dermatitis due to adhesives 
M1281 
Allergic contact dermatitis due to cosmetics 
M1282 
Allergic contact dermatitis due to drugs in contact with the skin 
M1283 
Allergic contact dermatitis due to dyes 
M1284 
Allergic contact dermatitis due to other chemical products 
M1285 
Allergic contact dermatitis due to food in contact with the skin 
M1286 
Allergic contact dermatitis due to plants, except food 
Myu21 
[X]Allergic contact dermatitis due to other chemical products 
Myu23 
[X]Allergic contact dermatitis due to other agents 
X5063 
Irritant contact dermatitis 
X504O 
Fibreglass dermatitis 
X5064 
Acute irritant contact dermatitis 
X5065 
Subacute irritant contact dermatitis 
X5066 
Chronic irritant contact dermatitis 
Xa0WJ 
Swimming pool dermatitis 
X505H 
Cactus dermatitis 
Xa13g 
Coral dermatitis 
M123. 
Drug-induced contact dermatitis 
M1230 
Contact dermatitis due to arnica 
M1231 
Contact dermatitis due to fungicides 
M1232 
Contact dermatitis due to iodine 
M1233 
Contact dermatitis due to keratolytics 
M1234 
Contact dermatitis due to mercurials 
M1235 
Contact dermatitis due to neomycin 
M1236 
Contact dermatitis due to pediculocides 
M1237 
Contact dermatitis due to phenols 
M1238 
Contact dermatitis due to scabicides 
M123z 
Contact dermatitis due to medicament NOS 
M1290 
Irritant contact dermatitis due to cosmetics 
M1291 
Irritant contact dermatitis due to drugs in contact with the skin 
M1292 
Irritant contact dermatitis due to other chemical products 
M1293 
Irritant contact dermatitis due to food in contact with the skin 
M1294 
Irritant contact dermatitis due to plants, except food 
Myu24 
[X]Irritant contact dermatitis due to other chemical products 
Myu25 
[X]Irritant contact dermatitis due to other agents 
X5062 
Occupational allergic contact dermatitis 

XE1Ar 
Contact dermatitis due to adhesive plaster 
X505t 
Elastoplast contact dermatitis 
M120. 
Contact dermatitis due to detergents 
M122. 
Contact dermatitis due to solvents 
M1220 
Contact dermatitis due to chlorocompound 
M1221 
Contact dermatitis due to cyclohexane 
M1222 
Contact dermatitis due to ester 
M1223 
Contact dermatitis due to glycol 
M1224 
Contact dermatitis due to hydrocarbon 
M1225 
Contact dermatitis due to ketone 
M122z 
Contact dermatitis due to solvent NOS 
M124. 
Contact dermatitis due to other chemical products 
M1240 
Contact dermatitis due to acids 
M1242 
Contact dermatitis due to alkalis 
M1243 
Contact dermatitis due to caustics 
M1244 
Contact dermatitis due to dichromate 
M1245 
Contact dermatitis due to insecticide 
M1246 
Contact dermatitis due to nylon 
M1247 
Contact dermatitis due to plastic 
M1248 
Contact dermatitis due to rubber 
M124z 
Contact dermatitis: other chemicals NOS 
M125. 
Contact dermatitis due to food in contact with skin 
M1250 
Contact dermatitis due to cereals 
M1251 
Contact dermatitis due to fish 
M1252 
Contact dermatitis due to flour 
M1253 
Contact dermatitis due to fruit 
M1254 
Contact dermatitis due to meat 
M1255 
Contact dermatitis due to milk 
X505u 
Egg contact dermatitis 
XE1As 
Contact dermatitis due to food NOS 
M126. 
Contact dermatitis due to plants 
M1260 
Contact dermatitis due to lacquer tree 
M1261 
Contact dermatitis due to poison-ivy 
M1262 
Contact dermatitis due to poison-oak 
M1263 
Contact dermatitis due to poison-sumac 
M1264 
Contact dermatitis due to poison-vine 
M1265 
Contact dermatitis due to primrose 
M1266 
Contact dermatitis due to ragweed 
M126z 
Contact dermatitis due to plants NOS 
M12y. 
Contact dermatitis due to other specified agents 
M12y1 
Contact dermatitis due to cold weather 
M12y2 
Contact dermatitis due to dyes 
M12y3 
Contact dermatitis due to furs 
M12y4 
Contact dermatitis due to hot weather 
M12y5 
Contact dermatitis due to infrared rays 
M12y6 
Contact dermatitis due to jewellery 
M12y7 
Contact dermatitis due to light (excluding sunlight) 

M12y9 
Contact dermatitis due to preservatives 
M12yA 
Contact dermatitis due to radiation NOS 
M12yB 
Contact dermatitis due to ultraviolet rays (excluding sunlight) 
M12yC 
Contact dermatitis due to X-rays 
M12yD 
Contact dermatitis due to casting materials 
M12yz 
Contact dermatitis: specified agent NOS 
X505v 
Lanolin contact dermatitis 
XE1At 
Contact dermatitis due to cosmetics 
X505w 
Perfume contact dermatitis 
XE1Au 
Contact dermatitis due to metals 
M12z. 
Contact dermatitis NOS 
Myu26 
[X]Unspecified contact dermatitis due to other chemical products 
Myu27 
[X]Unspecified contact dermatitis due to other agents 
XE1Aq 
Contact dermatitis due to oils and greases 
X505r 
Grease contact dermatitis 
X505s 
Oil contact dermatitis 
Xa3gI 
Contact dermatitis - chemicals 
Xa3gJ 
Contact dermatitis - foods/plants 
SNOMED CT ID 
Description 
10628511000119107 
Irritant contact dermatitis caused by detergent (disorder) 
10628551000119108 
Irritant contact dermatitis caused by rubber 
10628591000119103 
Irritant contact dermatitis caused by chemical (disorder) 
10628631000119103 
Irritant contact dermatitis caused by metal (disorder) 
10628671000119100 
Allergic contact dermatitis caused by latex (disorder) 
10628711000119101 
Allergic contact dermatitis caused by plant material (disorder) 
10628751000119100 
Allergic contact dermatitis caused by pollen (disorder) 
10676871000119103 
Allergic contact dermatitis caused by chemical (disorder) 
10761991000119101 
Contact dermatitis of right upper and lower eyelids (disorder) 
10901008 
Contact dermatitis caused by poison sumac (disorder) 
110979008 
Irritant contact dermatitis (disorder) 
111189002 
Acute contact dermatitis (disorder) 
111190006 
Contact dermatitis caused by phenol (disorder) 
111191005 
Contact dermatitis due to other drug, NEC (disorder) 
111192003 
Contact dermatitis caused by insecticide 
111193008 
Contact dermatitis due to other non food plant (disorder) 
111194002 
Contact dermatitis due to other specified agents (disorder) 
111209006 
Photoallergic contact dermatitis 
11804009 
Contact dermatitis caused by solar radiation (disorder) 
11873831000119107 
Contact dermatitis of bilateral lower eyelids 
123705009 
Generalized exfoliative contact dermatitis (disorder) 
126631000119108  
Contact dermatitis caused by adhesive bandage (disorder) 
13476007 
Contact dermatitis due to fur (disorder) 
156332005 
Urine-induced contact dermatitis (disorder) 
156338009 
Contact dermatitis/eczema 
156339001 
Contact dermatitis due to detergents (disorder) 
156340004 
Contact dermatitis due to oils and greases (disorder) 
156341000 
Contact dermatitis due to solvents (disorder) 

156342007 
Drug-induced contact dermatitis (disorder) 
156343002 
Contact dermatitis: [chemicals] or [elastoplast allergy] 
156344008 
Contact dermatitis - foods/plants (disorder) 
156345009 
(Contact dermatitis: sun) or (Farmers skin) or (photosensitivity - sun) or 
(sunburn) (disorder) 
156346005 
Contact dermatitis: metals(& [nickel]) (disorder) 
156348006 
(Contact dermatitis NOS) or (discoid eczema) or (nummular eczema) 
(disorder) 
15681161000119107 
Contact dermatitis of bilateral eyelids (disorder) 
16228891000119105  
Allergic contact dermatitis caused by metal (disorder) 
17946007 
Contact dermatitis caused by fungicide (disorder) 
18793008 
Contact dermatitis caused by fruit (disorder) 
193918001 
Contact &/or allergic eyelid dermatitis (disorder) 
200780008 
(Contact dermatitis [& other eczemas]) or (contact eczema) or (occupational 
dermatitis) (disorder) 
200781007 
Contact dermatitis due to detergents (disorder) 
200782000 
Contact dermatitis due to oils &/or greases (disorder) 
200783005 
Contact dermatitis due to solvents (disorder) 
200784004 
Contact dermatitis caused by chlorocompound 
200785003 
Contact dermatitis caused by cyclohexane group 
200786002 
Contact dermatitis caused by ester (disorder) 
200787006 
Contact dermatitis caused by glycol 
200788001 
Contact dermatitis caused by hydrocarbon (disorder) 
200789009 
Contact dermatitis caused by ketone (disorder) 
200790000 
Contact dermatitis due to solvent NOS (disorder) 
200791001 
Contact dermatitis due to arnica (disorder) 
200792008 
Contact dermatitis due to fungicides (disorder) 
200793003 
Contact dermatitis due to iodine (disorder) 
200794009 
Contact dermatitis caused by keratolytic 
200795005 
Contact dermatitis due to mercurials (disorder) 
200796006 
Contact dermatitis due to neomycin (disorder) 
200797002 
Contact dermatitis due to pediculicides (disorder) 
200798007 
Contact dermatitis due to phenols (disorder) 
200799004 
Contact dermatitis due to scabicides (disorder) 
200800000 
Contact dermatitis due to medicament NOS (disorder) 
200801001 
Contact dermatitis due to other chemical products (disorder) 
200802008 
Contact dermatitis caused by acid (disorder) 
200803003 
Contact dermatitis due to adhesive plaster (& elastoplast) (disorder) 
200804009 
Contact dermatitis caused by alkali (disorder) 
200805005 
Contact dermatitis due to caustic 
200806006 
Contact dermatitis due to dichromate (disorder) 
200807002 
Contact dermatitis due to insecticide (disorder) 
200808007 
Contact dermatitis due to nylon (disorder) 
200809004 
Contact dermatitis due to plastic (disorder) 
200810009 
Contact dermatitis due to rubber (disorder) 
200811008 
Contact dermatitis: other chemicals NOS (disorder) 
200813006 
Contact dermatitis due to food in contact with skin (disorder) 
200814000 
Contact dermatitis due to cereals (disorder) 

200815004 
Contact dermatitis due to fish (disorder) 
200816003 
Contact dermatitis due to flour (disorder) 
200817007 
Contact dermatitis due to fruit (disorder) 
200818002 
Contact dermatitis due to meat (disorder) 
200819005 
Contact dermatitis due to milk (disorder) 
200820004 
(Contact dermatitis due to food NOS) or (egg contact dermatitis) (disorder) 
200821000 
Contact dermatitis caused by plants 
200822007 
Contact dermatitis due to lacquer tree (disorder) 
200823002 
Contact dermatitis caused by poison ivy (disorder) 
200824008 
Contact dermatitis caused by poison oak 
200825009 
Contact dermatitis due to poison-sumac (disorder) 
200826005 
Contact dermatitis due to poison-vine (disorder) 
200827001 
Contact dermatitis due to primrose (disorder) 
200828006 
Contact dermatitis due to ragweed (disorder) 
200829003 
Contact dermatitis due to plants NOS (disorder) 
200830008 
Contact dermatitis due to solar radiation (disorder) 
200831007 
Unspecified contact dermatitis due to solar radiation (disorder) 
200836002 
Photocontact dermatitis 
200840006 
Contact dermatitis due to solar radn NOS (disorder) 
200841005 
Allergic contact dermatitis (disorder) 
200842003 
Allergic contact dermatitis due to adhesive 
200843008 
Allergic contact dermatitis due to cosmetic 
200844002 
Allergic contact dermatitis due to drug in contact with skin 
200845001 
Allergic contact dermatitis due to dye 
200846000 
Allergic contact dermatitis due to other chemical products (disorder) 
200847009 
Allergic contact dermatitis caused by food in contact with skin 
200848004 
Allergic contact dermatitis caused by plants, except food (disorder) 
200850007 
Irritant contact dermatitis (disorder) 
200851006 
Irritant contact dermatitis due to cosmetic 
200852004 
Irritant contact dermatitis due to drug in contact with skin 
200853009 
Irritant contact dermatitis due to other chemical products (disorder) 
200854003 
Irritant contact dermatitis due to food in contact with skin 
200855002 
Irritant contact dermatitis caused by plants, except food (disorder) 
200867000 
Contact dermatitis due to other specified agents (disorder) 
200869002 
Contact dermatitis due to cold weather (disorder) 
200870001 
Contact dermatitis due to dyes (disorder) 
200871002 
Contact dermatitis due to fur 
200872009 
Contact dermatitis due to hot weather (disorder) 
200873004 
Contact dermatitis due to infrared rays (disorder) 
200874005 
Contact dermatitis due to jewelry (disorder) 
200875006 
Contact dermatitis due to light (excluding sunlight) (disorder) 
200876007 
(Contact dermatitis due to metals) or (nickel sensitivity) (disorder) 
200877003 
Contact dermatitis caused by preservatives 
200878008 
Contact dermatitis due to radiation NOS (disorder) 
200879000 
Contact dermatitis caused by ultraviolet rays (excluding sunlight) 
200880002 
Contact dermatitis due to X-rays (disorder) 
200881003 
Contact dermatitis caused by casting materials 

200882005 
Contact dermatitis: specified agent NOS (disorder) 
200883000 
Contact dermatitis NOS (disorder) 
200889001 
Contact dermatitis NOS (disorder) 
201360000 
[X]Allergic contact dermatitis due to other chemical products (disorder) 
201361001 
[X]Allergic contact dermatitis due to other agents (disorder) 
201362008 
[X]Irritant contact dermatitis due to other chemical products (disorder) 
201363003 
[X]Irritant contact dermatitis due to other agents (disorder) 
201364009 
[X]Unspecified contact dermatitis due to other chemical products (disorder) 
201365005 
[X]Unspecified contact dermatitis due to other agents (disorder) 
22131007 
Contact dermatitis due to ultraviolet rays, except sun (disorder) 
22353002 
Contact dermatitis due to glycol group (disorder) 
23012005 
Contact dermatitis caused by solvents 
238506004 
Contact dermatitis due to cold weather 
238524002 
Photoallergic contact dermatitis 
238568000 
Grease contact dermatitis (disorder) 
238569008 
Oil contact dermatitis (disorder) 
238570009 
Elastoplast contact dermatitis (disorder) 
238571008 
Egg contact dermatitis (disorder) 
238572001 
Lanolin contact dermatitis (disorder) 
238573006 
Perfume contact dermatitis (disorder) 
238575004 
Allergic contact dermatitis (disorder) 
238576003 
Allergic contact dermatitis caused by nickel implant (disorder) 
238577007 
Ingested allergen contact dermatitis (disorder) 
238578002 
Occupational allergic contact dermatitis (disorder) 
238579005 
Acute irritant contact dermatitis (disorder) 
238580008 
Subacute irritant contact dermatitis (disorder) 
238581007 
Chronic irritant contact dermatitis (disorder) 
238583005 
Saliva-induced contact dermatitis (disorder) 
238584004 
Feces-induced contact dermatitis (disorder) 
238672005 
Lichenoid allergic contact dermatitis (disorder) 
247469006 
Urine-induced contact dermatitis (disorder) 
25664003 
Contact dermatitis due to dichlorvos 
26208004 
Contact dermatitis due to keratolytic agent (disorder) 
26532007 
Contact dermatitis caused by scabicide (disorder) 
267648006 
Contact or allergic eyelid dermatitis (disorder) 
267792000 
Contact dermatitis and other eczemas (disorder) 
267793005 
Contact dermatitis due to oil and grease 
267794004 
Contact dermatitis due to food NOS (disorder) 
267795003 
Contact dermatitis due to cosmetics (disorder) 
267796002 
Contact dermatitis due to metal (disorder) 
267842005 
Contact dermatitis/eczema (& [allergic eczema - extrinsic] or [occupational 
eczema]) 
267843000 
Contact dermatitis: [chemicals] or [elastoplast allergy] 
267844006 
(Contact dermatitis: sun) or (Farmers skin) or (photosensitivity - sun) or 
(sunburn) (disorder) 
267845007 
Contact dermatitis: metals(& [nickel]) (disorder) 
279334008 
Contact dermatitis due to infra-red rays 
287003002 
Contact dermatitis - chemicals (disorder) 

287004008 
Contact dermatitis - foods/plants (disorder) 
2889003 
Contact dermatitis due to alkali (disorder) 
291000119100 
Contact dermatitis caused by chemical (disorder) 
30451004 
Contact dermatitis due to detergent 
31948006 
Contact dermatitis caused by plastic (disorder) 
3226008 
Contact dermatitis - chemicals 
32371003 
Contact dermatitis caused by neomycin (disorder) 
342761000119104 
Allergic contact dermatitis of right upper eyelid (disorder) 
342771000119105 
Allergic contact dermatitis of right lower eyelid 
342781000119108 
Allergic contact dermatitis of right eyelid (disorder) 
342791000119106 
Allergic contact dermatitis of left upper eyelid 
342801000119107 
Allergic contact dermatitis of left lower eyelid (disorder) 
342811000119105 
Allergic contact dermatitis of left eyelid (disorder) 
36530008 
Contact dermatitis caused by fish 
39670009 
Contact dermatitis due to chlorocompound group (disorder) 
402249007 
Allergic contact dermatitis of eyelid 
402252004 
Allergic contact dermatitis of perianal skin 
402253009 
Allergic contact dermatitis of external ear 
402254003 
Allergic contact dermatitis of hands 
402255002 
Allergic contact dermatitis of lower leg 
402256001 
Allergic contact dermatitis of male genitalia 
402257005 
Allergic contact dermatitis of female genitalia 
402261004 
Acute irritant contact dermatitis 
402263001 
Cumulative irritant contact dermatitis of hands caused by wet work 
402265008 
Irritant contact dermatitis of hands caused by oil and/or grease (disorder) 
402266009 
Irritant contact dermatitis of hands caused by solvent 
402267000 
Irritant contact dermatitis caused by metal swarf (disorder) 
402268005 
Irritant contact dermatitis caused by cement (disorder) 
402269002 
Irritant contact dermatitis of hands caused by cement (disorder) 
402270001 
Irritant contact dermatitis of hands caused by friction 
402271002 
Irritant contact dermatitis caused by chlorine 
402272009 
Irritant contact dermatitis caused by biocide (disorder) 
402273004 
Cumulative irritant contact dermatitis of hands 
402274005 
Cumulative irritant contact dermatitis 
402275006 
Irritant contact dermatitis caused by contact with urine and/or feces 
(disorder) 
402276007 
Irritant contact dermatitis due to incontinence 
402278008 
Irritant contact dermatitis due to stoma/fistula 
402279000 
Irritant contact dermatitis due to ileostomy 
402280002 
Irritant contact dermatitis due to colostomy 
402281003 
Irritant contact dermatitis due to urostomy 
402284006 
Irritant contact dermatitis due to dribbling and/or teething 
402290005 
Irritant contact hand dermatitis 
402291009 
Contact dermatitis of hands 
402577002 
Allergic contact dermatitis by site 
402578007 
Irritant contact dermatitis caused by detergent and/or wet work (disorder) 
402579004 
Irritant contact dermatitis caused by plant 

402580001 
Irritant contact dermatitis caused by oil and/or grease (disorder) 
402581002 
Irritant contact dermatitis caused by wood (disorder) 
402582009 
Irritant contact dermatitis caused by solvent (disorder) 
402584005 
Occupational irritant contact dermatitis 
40275004 
Contact dermatitis and other eczemas 
403585004 
Contact psychodermatitis 
405244005 
Urine induced contact dermatitis 
40712008 
Contact dermatitis caused by arnica 
409784006 
Contact dermatitis caused by Rhus diversiloba (disorder) 
409785007 
Contact dermatitis caused by Rhus quercifolia 
410049000 
Contact dermatitis caused by Genus Toxicodendron 
419121001 
Allergic contact dermatitis of pinna 
419957005 
Allergic contact dermatitis of external auditory canal 
42409002 
Contact dermatitis due to oils (disorder) 
425630003 
Acute irritant contact dermatitis 
42733007 
Contact dermatitis caused by dichromate 
44210006 
Contact dermatitis due to preservative (disorder) 
45309006 
Allergic contact dermatitis caused by secretions (disorder) 
46240005 
Contact dermatitis caused by rubber (disorder) 
46787004 
Contact dermatitis caused by light, except sun (disorder) 
48681004 
Contact dermatitis due to hot weather (disorder) 
49186001 
Contact dermatitis caused by cereal (disorder) 
51221005 
Chronic contact dermatitis (disorder) 
51732009 
Contact dermatitis due to hydrocarbon group (disorder) 
5205006 
Contact dermatitis due to poison ivy (disorder) 
5221001 
Contact dermatitis due to greases (disorder) 
52811009 
Contact dermatitis due to ketone group (disorder) 
53930004 
Contact dermatitis caused by ragweed (disorder) 
55113003 
Contact dermatitis due to poison oak (disorder) 
55934006 
Contact dermatitis caused by flour 
56669003 
Contact dermatitis due to ester group (disorder) 
586008 
Contact dermatitis caused by primrose (disorder) 
58843002 
Contact dermatitis due to caustic agent (disorder) 
59336008 
Contact dermatitis due to cold weather (disorder) 
64451001 
Contact dermatitis due to cyclohexane group (disorder) 
65129009 
Contact dermatitis caused by milk 
65394002 
Contact dermatitis caused by Rhus verniciflua 
67445002 
Contact dermatitis caused by food in contact with skin (disorder) 
67607005 
Contact dermatitis due to infrared rays (disorder) 
68670009 
Contact dermatitis of eyelid (disorder) 
6888008 
Contact dermatitis caused by dye (disorder) 
69827001 
Contact dermatitis due to X-ray 
69999007 
Contact dermatitis caused by plants, except food 
700340008 
Allergic contact dermatitis of upper eyelid (disorder) 
700341007 
Allergic contact dermatitis of lower eyelid 
715150009 
Contact dermatitis caused by Senecio jacobea 
717724001 
Irritant contact dermatitis of female genitalia 

717725000 
Contact dermatitis of female genitalia 
72057009 
Contact dermatitis caused by pediculicide 
724635009 
Contact dermatitis of external ear 
724825001 
Allergic contact dermatitis caused by hairdressing product (disorder) 
724828004 
Irritant contact dermatitis caused by cosmetic substance 
724829007 
Occupational contact dermatitis 
724869008 
Protein contact dermatitis 
72921001 
Contact dermatitis caused by meat 
733201000 
Irritant contact dermatitis caused by dietary substance (disorder) 
735758003 
Irritant contact dermatitis caused by friction 
735759006 
Irritant contact dermatitis caused by sweat 
735760001 
Irritant contact dermatitis caused by body fluid 
762379000 
Allergic contact dermatitis caused by dental material (disorder) 
762380002 
Allergic contact dermatitis caused by food flavour 
762381003 
Allergic contact dermatitis caused by food additive (disorder) 
762382005 
Allergic contact dermatitis caused by agrochemical biocide 
762383000 
Allergic contact dermatitis caused by cutting oil 
762384006 
Allergic contact dermatitis caused by disinfectant (disorder) 
762385007 
Allergic contact dermatitis caused by allergenic hapten derived from plants 
or organic matter 
762386008 
Allergic contact dermatitis caused by rubber compound 
762387004 
Allergic contact dermatitis caused by systemic medicament 
762388009 
Irritant contact dermatitis caused by emollient substance (disorder) 
762545002 
Occupational allergic contact dermatitis caused by footwear (disorder) 
762548000 
Occupational allergic contact dermatitis caused by cosmetic 
762549008 
Occupational allergic contact dermatitis caused by fragrance 
762552000 
Occupational allergic contact dermatitis caused by dental material 
762554004 
Occupational allergic contact dermatitis caused by food flavor 
762555003 
Occupational allergic contact dermatitis caused by food additive (disorder) 
762558001 
Occupational allergic contact dermatitis caused by hairdressing product 
(disorder) 
762560004 
Occupational allergic contact dermatitis caused by agrochemical biocide 
(disorder) 
762561000 
Occupational allergic contact dermatitis caused by cutting oil 
762562007 
Occupational allergic contact dermatitis caused by disinfectant (disorder) 
762566005 
Occupational allergic contact dermatitis caused by metal compound 
762568006 
Occupational allergic contact dermatitis caused by allergenic hapten derived 
from plant (disorder) 
762570002 
Occupational allergic contact dermatitis caused by industrial preservative 
(disorder) 
762571003 
Occupational allergic contact dermatitis caused by biocide 
762574006 
Occupational allergic contact dermatitis caused by rubber compound 
762576008 
Occupational allergic contact dermatitis caused by systemic drug or 
medicament 
762578009 
Occupational allergic contact dermatitis caused by topical medicament 
(disorder) 
762726008 
Occupational allergic contact dermatitis caused by clothing 
762754001 
Allergic contact dermatitis caused by fragrance (disorder) 
762755000 
Allergic contact dermatitis caused by footwear (disorder) 
762757008 
Allergic contact dermatitis caused by clothing 

76982008 
Contact dermatitis due to poison vine 
770545005 
Allergic contact dermatitis caused by iodine (disorder) 
770588002 
Allergic contact dermatitis caused by iodophore (disorder) 
770589005 
Allergic contact dermatitis caused by povidone iodine (disorder) 
77560002 
Contact dermatitis due to adhesive plaster 
78079005 
Allergic contact dermatitis due to excretions 
78634007 
Contact dermatitis due to metal 
78755001 
Contact dermatitis due to cosmetics 
788971005 
Irritant contact dermatitis of external ear (disorder) 
79927003 
Contact dermatitis due to acid (disorder) 
81351008 
Contact dermatitis caused by radiation (disorder) 
81581001 
Contact dermatitis due to mercurials 
83150005 
Contact dermatitis due to iodine 
83508001 
Contact dermatitis due to nylon 
85512009 
Contact dermatitis due to jewellery 
86062001 
Contact dermatitis caused by drugs AND/OR medicine 
860924005 
Allergic contact dermatitis caused by alkali-metal soap (disorder) 
870749003 
Allergic contact dermatitis caused by usnic acid (disorder) 
88718007 
Subacute contact dermatitis 
91487003 
Urine-induced contact dermatitis 
93418006 
Contact dermatitis due to chromium 
93419003 
Contact dermatitis due to metals 
10762031000119106 
Contact dermatitis of left upper and lower eyelids (disorder)  
Photodermatitis 
Read V2 Code 
Code description 
M1273 
Photodermatitis 
M1274 
Photosensitiveness 
M1278 
Photocontact dermatitis [berloque dermatitis] 
M1279 
Hydroa vacciniforme 
M12A0 
Drug phototoxic response 
M12A1 
Drug photoallergic response 
M1272 
Hydroa aestivale 
Read CTV3 Code 
Description 
M1273 
Photodermatitis 
M1274 
Photosensitivity of skin 
X504r 
Photosensitisation reaction 
X504z 
Hydroa vacciniforme 
X50Gr 
Drug-induced photosensitivity 
X50Gs 
Drug phototoxic response 
X50Gt 
Drug photoallergic response 
Xa0Wh 
Drug-induced persistent light reaction 
M1272 
Hydroa aestivale 
SNOMED CT ID 
Description 
111209006 
Photoallergic dermatitis 
123240009 
Photodermatitis due to sun 
12477008 
Acute phototoxic dermatitis 
12761008 
Acute photoallergic dermatitis 

200832000 
Hydroa aestivale 
200836002 
Photocontact dermatitis [berloque dermatitis] 
200837006 
Hydroa vacciniforme 
200857005 
Drug phototoxic response 
200858000 
Drug photoallergic response 
201015007 
Hydroa aestivale 
22649008 
Photodermatitis 
238521005 
Plant photodermatitis 
238523008 
Photoallergic eczema 
238524002 
Photoallergic contact dermatitis 
238525001 
Polymorphic photodermatitis 
238527009 
Persistent light reaction 
259097007 
Delayed photoallergic dermatitis 
259608005 
Photodermatitis due to sun 
27687007 
Hydroa aestivale 
277805004 
Drug-induced persistent light reaction 
363619000 
Phototoxic phytotoxin 
367334003 
Photoallergic eczema 
367484009 
Photodermatitis due to sun 
402168004 
Acute phototoxic reaction (disorder) 
402172000 
Hypermelanosis due to phytophotodermatitis (disorder) 
402173005 
Phototoxic reaction to topical chemical (disorder) 
402174004 
Phototoxic reaction to dye (disorder) 
402175003 
Phototoxic reaction to tar or derivatives (disorder) 
402176002 
Phototoxic reaction to topically applied medicament (disorder) 
402480004 
Porphyria-induced phototoxic burn (disorder) 
44483004 
Phytophotodermatitis 
450907007 
Hydroa vacciniforme-like lymphoma (morphologic abnormality) 
45832002 
Pupil afferent light reaction 
53597009 
Phototoxic dermatitis 
58306008 
Acute phytophotodermatitis 
58419006 
Chronic phytophotodermatitis 
61064008 
Photodermatitis due to sun 
69231004 
Chronic phototoxic dermatitis 
724873006 
Occupational phototoxic reaction to skin contact with exogenous 
photoactive agent (disorder) 
737249005 
Photodermatitis co-occurrent and due to autoimmune disease (disorder) 
737250005 
Phototoxic reaction of skin caused by fragrance (disorder) 
737251009 
Phototoxic reaction of skin caused by cosmetic 
763719001 
Hydroa vacciniforme-like lymphoma (disorder) 
789440003 
Hydroa vacciniforme-like lymphoproliferative disorder 
80346008 
Drug photoallergic response 
83627000 
Drug phototoxic response 
84326006 
Phototoxicity 
95349002 
Phytophotodermatitis due to topical exposure to furocoumarin (disorder) 
Ichthyosis 
Read V2 Code 
Code description 

M211. 
Ichthyosis - acquired 
M2116 
Acquired ichthyosis 
PH1.. 
Ichthyosis congenita 
PH10. 
Congenital ichthyosis, unspecified 
PH11. 
Harlequin fetus 
PH12. 
Ichthyosiform erythroderma 
PH13. 
Collodion baby 
PH14. 
Ichthyosis vulgaris 
PH15. 
X-linked ichthyosis 
PH1y. 
Other specified ichthyosis congenita 
PH1y0 
Nethertons syndrome 
PH1z. 
Ichthyosis congenita NOS 
Read CTV3 Code 
Description 
PH1.. 
Congenital ichthyosis 
X78C8 
Ichthyosis vulgaris 
X78C9 
Autosomal dominant ichthyosis vulgaris 
X78CB 
X-linked recessive ichthyosis 
X78CA 
Severe ichthyoses 
PH13. 
Lamellar ichthyosis 
X78CD 
Erythrodermic lamellar ichthyosis 
X78CE 
Non-erythrodermic lamellar ichthyosis 
X78CF 
Autosomal dominant lamellar ichthyosis 
X78CG 
Non-bullous ichthyosiform erythroderma 
X3085 
Ichthyosis congenita with biliary atresia 
X78CH 
Bullous ichthyosis 
X78CI 
Bullous ichthyosiform erythroderma 
X78CJ 
Localised bullous ichthyosiform erythroderma 
X78CK 
Ichthyosis bullosa of Siemens 
PH11. 
Harlequin ichthyosis 
X78CL 
Ichthyosis hystrix 
X78CM 
Ichthyosis hystrix of Curth-Macklin 
X78CN 
Maleformatio ectodermalis generalisata of Bafverstedt 
X78CO 
Ichthyosis hystrix gravior of Rheydt 
X78CP 
Hystrix ichthyosis with deafness 
X78CQ 
Porcupine man 
PH10. 
Congenital ichthyosis, unspecified 
PH1y. 
Other specified ichthyosis congenita 
XE1ML 
Ichthyosis congenita NOS 
Pyu90 
[X]Other congenital ichthyosis 
XE1MK 
Ichthyosiform erythroderma 
X78C7 
Congenital ichthyosiform erythroderma 
X507Q 
Acquired ichthyosis 
X50IK 
Keratitis ichthyosis and deafness syndrome 
X50IM 
Atypical ichthyosis vulgaris with hypogonadism 
X78BT 
Nethertons syndrome 
SNOMED CT ID 
Description 
111303009 
Ichthyosiform erythroderma 

12215009 
Recessive congenital ichthyosiform erythroderma 
13059002 
Ichthyosis congenita 
157017000 
Integument anomalies: [ichthyosis congenita] or [Dariers] or [keratosis 
follicularis] or [Meiges] or [Milroys] or [Mongolian spots] or 
[pseudoxanthoma elasticum] or [congenital NOS] 
19604005 
Triglyceride storage disease with ichthyosis 
201053002 
(Acquired ichthyosis) or (acquired keratoderma) or (hyperkeratosis NOS) 
201058006 
Acquired ichthyosis 
20512000 
Dominant congenital ichthyosiform erythroderma 
205547001 
Congenital ichthyosis, unspecified 
205548006 
Harlequin ichthyosis 
205549003 
Ichthyosiform erythroderma 
205550003 
Collodion baby 
205551004 
Ichthyosis vulgaris 
205552006 
X-linked recessive ichthyosis 
205553001 
Other specified ichthyosis congenita 
205555008 
Nethertons syndrome 
205556009 
(Congenital ichthyosiform erythroderma) or (alligator skin) or (ichthyosis 
congenita NOS) 
205974009 
[X]Other congenital ichthyosis 
2355008 
Dwarfism-ichthyosiform erythroderma-mental deficiency syndrome 
235916001 
Ichthyosis congenita with biliary atresia 
238627002 
Follicular ichthyosis 
238997007 
Drug-induced ichthyosiform reaction 
239057002 
Cutaneous syndrome with ichthyosis 
239058007 
Nethertons syndrome 
239059004 
Keratitis ichthyosis and deafness syndrome 
239060009 
Atypical ichthyosis vulgaris with hypogonadism 
239061008 
Keratosis pilaris with ichthyosis and deafness 
254127001 
Nethertons syndrome 
254128006 
Recessive congenital ichthyosiform erythroderma 
254156001 
Ichthyosis congenita NOS 
254157005 
Ichthyosis vulgaris 
254158000 
Autosomal dominant ichthyosis vulgaris 
254160003 
X-linked recessive ichthyosis 
254161004 
Erythrodermic lamellar ichthyosis 
254163001 
Non-erythrodermic lamellar ichthyosis 
254164007 
Autosomal dominant lamellar ichthyosis 
254165008 
Non-bullous ichthyosiform erythroderma 
254166009 
Bullous ichthyosis 
254167000 
Bullous ichthyosiform erythroderma 
254168005 
Localised bullous ichthyosiform erythroderma 
254169002 
Ichthyosis bullosa of Siemens 
254170001 
Ichthyosis hystrix of Curth-Macklin 
254171002 
Maleformatio ectodermalis generalisata of Bafverstedt 
254172009 
Ichthyosis hystrix gravior of Rheydt 
254173004 
Hystrix ichthyosis with deafness 
254174005 
Porcupine man 

255425009 
Ichthyosiform 
2625009 
Keratosis-ichthyosis-deafness syndrome 
267372009 
Congenital non bullous ichthyosiform erythroderma 
268245001 
Harlequin fetus 
268282005 
Ichthyosiform erythroderma 
268283000 
Ichthyosis congenita NOS 
268355000 
Ichthyosis congenita 
312514006 
Nethertons syndrome 
34638006 
Lamellar ichthyosis AND trichorrhexis invaginata syndrome 
3944006 
X-linked ichthyosis 
396228006 
Ichthyosis - acquired 
400166009 
Ichthyosis - acquired 
402368008 
Ichthyosiform sarcoidosis (disorder) 
402770002 
Autosomal dominant ichthyosis (disorder) 
402771003 
X-linked recessive ichthyosis (disorder) 
402772005 
Autosomal recessive ichthyosis (disorder) 
403777006 
Lamellar ichthyosis (limited type) (disorder) 
403778001 
X-linked dominant ichthyosis (Happle) 
403779009 
Ichthyosis, cerebellar degeneration and hepatosplenomegaly (disorder) 
403780007 
Autosomal recessive keratitis-ichthyosis-deafness syndrome (disorder) 
403781006 
Photosensitivity with ichthyosis, brittle hair, impaired intelligence, 
decreased fertility and short stature syndrome 
403782004 
Ichthyosis follicularis with alopecia and photophobia (IFAP) (disorder) 
54336006 
Ichthyosis linearis circumflexa 
55846006 
Ichthyosis of eyelid 
67510007 
Ichthyosis hystrix 
68551007 
Limb reduction-ichthyosis syndrome 
699315005 
Neutral lipid storage disease without ichthyosis 
703504006 
Congenital reticular ichthyosiform erythroderma (disorder) 
716097001 
Ichthyosis cheek eyebrow syndrome (disorder) 
717041008 
Syndromic recessive X-linked ichthyosis (disorder) 
717183001 
Keratoderma hereditarium mutilans with ichthyosis syndrome (disorder) 
718631006 
Annular epidermolytic ichthyosis (disorder) 
720639008 
Coloboma, congenital heart disease, ichthyosiform dermatosis, intellectual 
disability ear anomaly syndrome (disorder) 
722035007 
Intellectual disability, enteropathy, deafness, peripheral neuropathy, 
ichthyosis, keratoderma syndrome (disorder) 
722114007 
Osteosclerosis, ichthyosis, premature ovarian failure syndrome 
722385008 
Cerebral dysgenesis, neuropathy, ichthyosis, palmoplantar keratoderma 
syndrome (disorder) 
724277002 
Congenital ichthyosis with hypotrichosis syndrome (disorder) 
724278007 
Neonatal sclerosing cholangitis, ichthyosis, hypotrichosis syndrome 
(disorder) 
724837004 
Keratinopathic ichthyosis (disorder) 
72523005 
Sex-linked ichthyosis 
725588002 
Bathing suit ichthyosis (disorder) 
732950006 
Ichthyosis, oral and digital anomalies syndrome 
732952003 
Congenital cataract ichthyosis syndrome 
733028000 
Multiple sclerosis, ichthyosis, factor VIII deficiency syndrome 

733097003 
Ichthyosis, intellectual disability, dwarfism, renal impairment syndrome 
(disorder) 
763401009 
Congenital ichthyosis type 4 
763404001 
Ichthyosis, alopecia, eclabion, ectropion, intellectual disability syndrome 
763768001 
Autosomal recessive exfoliative ichthyosis (disorder) 
763775000 
Keratosis linearis, ichthyosis congenita, sclerosing keratoderma syndrome 
(disorder) 
765471005 
X-linked intellectual disability, hypogonadism, ichthyosis, obesity, short 
stature syndrome 
782957005 
Ichthyosis 
783551005 
Ichthyosis, short stature, brachydactyly, microspherophakia syndrome 
8691004 
Ichthyosis - acquired 
95334005 
Senile ichthyosis 
 
 
 

Appendix 3 
Diagnosis codes which will be used to identify VTE events. 
Pulmonary Embolism 
Read V2 Code 
Code description 
G401. 
Pulmonary embolism 
G4010 
Post operative pulmonary embolus 
G4011 
Recurrent pulmonary embolism 
L43.. 
Obstetric pulmonary embolism 
L432. 
Obstetric blood-clot pulmonary embolism 
L4320 
Obstetric blood-clot pulmonary embolism unspecified 
L4321 
Obstetric blood-clot pulmonary embolism - delivered 
L4322 
Obstetric blood-clot pulmonary embolism - delivered with postnatal 
complication 
L4323 
Obstetric blood-clot pulmonary embolism with antenatal complication 
L4324 
Obstetric blood-clot pulmonary embolism with postnatal complication 
L432z 
Obstetric blood-clot pulmonary embolism NOS 
L43y. 
Other obstetric pulmonary embolism 
L43y0 
Other obstetric pulmonary embolism unspecified 
L43y1 
Other obstetric pulmonary embolism - delivered 
L43y2 
Other obstetric pulmonary embolism - delivered with postnatal 
complication 
L43y3 
Other obstetric pulmonary embolism with antenatal complication 
L43y4 
Other obstetric pulmonary embolism with postnatal complication 
L43yz 
Other obstetric pulmonary embolism NOS 
L43z. 
Obstetric pulmonary embolism NOS 
L43z0 
Obstetric pulmonary embolism NOS, unspecified 
L43z1 
Obstetric pulmonary embolism NOS - delivered 
L43z2 
Obstetric pulmonary embolism NOS - delivered with postnatal 
complication 
L43z3 
Obstetric pulmonary embolism NOS with antenatal complication 
L43z4 
Obstetric pulmonary embolism NOS with postnatal complication 
L43zz 
Obstetric pulmonary embolism NOS 
L0964 
Pulmonary embolism following abortive pregnancy 
Read CTV3 Code 
Description 
XE0Um 
Pulmonary embolus 
XaOYV 
Recurrent pulmonary embolism 
X202x 
Pulmonary thromboembolism 
X202y 
Acute massive pulmonary embolism 
X202z 
Subacute massive pulmonary embolism 
G4010 
Postoperative pulmonary embolus 
L43.. 
Obstetric pulmonary embolism 
L432. 
Obstetric blood-clot pulmonary embolism 
L4320 
Obstetric blood-clot pulmonary embolism unspecified 
L4321 
Obstetric blood-clot pulmonary embolism - delivered 
L4322 
Obstetric blood-clot pulmonary embolism - delivered with postnatal 
complication 
L4323 
Obstetric blood-clot pulmonary embolism with antenatal complication 

L4324 
Obstetric blood-clot pulmonary embolism with postnatal complication 
L432z 
Obstetric blood-clot pulmonary embolism NOS 
L43z. 
Obstetric pulmonary embolism NOS 
L43z0 
Obstetric pulmonary embolism NOS, unspecified 
L43z1 
Obstetric pulmonary embolism NOS - delivered 
L43z2 
Obstetric pulmonary embolism NOS - delivered with postnatal 
complication 
L43z3 
Obstetric pulmonary embolism NOS with antenatal complication 
L43z4 
Obstetric pulmonary embolism NOS with postnatal complication 
XE0xN 
Other obstetric pulmonary embolism 
L43y0 
Other obstetric pulmonary embolism unspecified 
L43y1 
Other obstetric pulmonary embolism - delivered 
L43y2 
Other obstetric pulmonary embolism - delivered with postnatal 
complication 
L43y3 
Other obstetric pulmonary embolism with antenatal complication 
L43y4 
Other obstetric pulmonary embolism with postnatal complication 
L43yz 
Other obstetric pulmonary embolism NOS 
X012b 
Operation for pulmonary embolism 
X012c 
Embolectomy of pulmonary artery 
7A0A1 
Percutaneous embolectomy of pulmonary artery 
7A093 
Open pulmonary embolectomy 
X012d 
Transluminal fragmentation of pulmonary embolus 
XaBMd 
[V] Personal history of pulmonary embolism 
L0964 
Pulmonary embolism following abortive pregnancy 
14AC. 
H/O: pulmonary embolus 
SNOMED CT ID 
Description 
155326007 
(Pulmonary embolism) or (pulmonary infarct) (disorder) 
308159008 
[V] Personal history of pulmonary embolism 
315761003 
[V] Personal history of pulmonary embolism 
50206009 
Abortion with pulmonary embolism 
706870000 
Acute pulmonary embolism 
17263003 
Amniotic fluid pulmonary embolism 
200294005 
Amniotic fluid pulmonary embolism - delivered (disorder) 
200295006 
Amniotic fluid pulmonary embolism - delivered with postnatal 
complication (disorder) 
200298008 
Amniotic fluid pulmonary embolism NOS (disorder) 
200293004 
Amniotic fluid pulmonary embolism unspecified (disorder) 
200296007 
Amniotic fluid pulmonary embolism with antenatal complication 
(disorder) 
200297003 
Amniotic fluid pulmonary embolism with postnatal complication 
(disorder) 
233936003 
AMPE - Acute massive pulmonary embolism 
133971000119108 
Chronic pulmonary embolism 
58123006 
Failed attempted abortion with pulmonary embolism 
430801003 
Family history of pulmonary embolism (situation) 
10761511000119101 
History of pulmonary embolism on long-term anticoagulation therapy 
55589000 
Illegal abortion with pulmonary embolism 
441746000 
Infarction of lung due to iatrogenic pulmonary embolism 
51096002 
Legal abortion with pulmonary embolism 

200288002 
Obstetric air pulmonary embolism - delivered (disorder) 
200289005 
Obstetric air pulmonary embolism - delivered with postnatal 
complication (disorder) 
200286003 
Obstetric air pulmonary embolism (disorder) 
200292009 
Obstetric air pulmonary embolism NOS (disorder) 
200287007 
Obstetric air pulmonary embolism unspecified (disorder) 
200290001 
Obstetric air pulmonary embolism with antenatal complication 
(disorder) 
200291002 
Obstetric air pulmonary embolism with postnatal complication 
(disorder) 
200301007 
Obstetric blood-clot pulmonary embolism - delivered (disorder) 
200302000 
Obstetric blood-clot pulmonary embolism - delivered with postnatal 
complication 
200299000 
Obstetric blood-clot pulmonary embolism (disorder) 
200305003 
Obstetric blood-clot pulmonary embolism NOS 
200300008 
Obstetric blood-clot pulmonary embolism unspecified (disorder) 
200303005 
Obstetric blood-clot pulmonary embolism with antenatal complication 
200304004 
Obstetric blood-clot pulmonary embolism with postnatal complication 
237341004 
Obstetric pulmonary embolism 
156273009 
Obstetric pulmonary embolism (disorder) 
200320009 
Obstetric pulmonary embolism NOS 
200326003 
Obstetric pulmonary embolism NOS 
200322001 
Obstetric pulmonary embolism NOS - delivered 
200323006 
Obstetric pulmonary embolism NOS - delivered with postnatal 
complication 
200324000 
Obstetric pulmonary embolism NOS with antenatal complication 
200325004 
Obstetric pulmonary embolism NOS with postnatal complication 
200321008 
Obstetric pulmonary embolism NOS, unspecified 
267284008 
Obstetric pyaemic and septic pulmonary embolism 
200308001 
Obstetric pyaemic and septic pulmonary embolism - delivered 
200312007 
Obstetric pyaemic and septic pulmonary embolism NOS 
200310004 
Obstetric pyaemic and septic pulmonary embolism with antenatal 
complication 
200306002 
Obstetric pyemic and septic pulmonary embolism 
200309009 
Obstetric pyemic and septic pulmonary embolism - delivered with 
postnatal complication 
200307006 
Obstetric pyemic and septic pulmonary embolism unspecified 
200311000 
Obstetric pyemic and septic pulmonary embolism with postnatal 
complication 
50286006 
Obstetrical pulmonary embolism 
233217004 
Operation for pulmonary embolism 
200313002 
Other obstetric pulmonary embolism 
267285009 
Other obstetric pulmonary embolism 
200315009 
Other obstetric pulmonary embolism - delivered (disorder) 
200316005 
Other obstetric pulmonary embolism - delivered with postnatal 
complication (disorder) 
200319003 
Other obstetric pulmonary embolism NOS 
200314008 
Other obstetric pulmonary embolism unspecified (disorder) 
200317001 
Other obstetric pulmonary embolism with antenatal complication 
200318006 
Other obstetric pulmonary embolism with postnatal complication 

45015000 
Other obstetrical pulmonary embolism, NEC 
200284000 
Puerperal pulmonary embolism 
194882001 
Pulmonary embolism 
266292008 
Pulmonary embolism 
59282003 
Pulmonary embolism 
723859005 
Pulmonary embolism as current complication following acute 
myocardial infarction (disorder) 
860680001 
Pulmonary embolism due to and following ectopic pregnancy 
860681002 
Pulmonary embolism due to and following molar pregnancy (disorder) 
198855003 
Pulmonary embolism following abortive pregnancy 
663008 
Pulmonary embolism following molar AND/OR ectopic pregnancy 
10759311000119104 
Pulmonary embolism in childbirth (disorder) 
713078005 
Pulmonary embolism on long-term anticoagulation therapy (disorder) 
1001000119102 
Pulmonary embolism with infarction 
438773007 
Recurrent pulmonary embolism (disorder) 
441557008 
Septic pulmonary embolism 
82153002 
Spontaneous abortion with pulmonary embolism 
233937007 
Subacute massive pulmonary embolism 
417113001 
Suspected pulmonary embolism (context-dependent category) 
609480009 
Termination of pregnancy complicated by pulmonary embolism 
82153002 
 Miscarriage with pulmonary embolism (disorder) 
860681002 
Pulmonary embolism due to and following molar pregnancy (disorder) 
Deep Vein Thrombosis 
Read V2 Code 
Code description 
G801. 
Deep vein thrombosis 
G8010 
Phlebitis of the femoral vein 
G8011 
Phlebitis of the popliteal vein 
G8012 
Phlebitis of the anterior tibial vein 
G8013 
Phlebitis of the dorsalis pedis vein 
G8014 
Phlebitis of the posterior tibial vein 
G8015 
Deep vein phlebitis of the leg unspecified 
G8016 
Thrombophlebitis of the femoral vein 
G8017 
Thrombophlebitis of the popliteal vein 
G8018 
Thrombophlebitis of the anterior tibial vein 
G8019 
Thrombophlebitis of the dorsalis pedis vein 
G801A 
Thrombophlebitis of the posterior tibial vein 
G801B 
Deep vein thrombophlebitis of the leg unspecified 
G801C 
Deep vein thrombosis of leg related to air travel 
G801D 
Deep vein thrombosis of lower limb 
G801E 
Deep vein thrombosis of leg related to intravenous drug use 
G801F 
Deep vein thrombosis of peroneal vein 
G801G 
Recurrent deep vein thrombosis 
G801H 
Unprovoked deep vein thrombosis 
G801J 
Provoked deep vein thrombosis 
G801z 
Deep vein phlebitis and thrombophlebitis of the leg NOS 
8CMWA 
On deep vein thrombosis care pathway 
SP122 
Post operative deep vein thrombosis 

L414. 
Postnatal deep vein thrombosis 
L4140 
Postnatal deep vein thrombosis unspecified 
L4141 
Postnatal deep vein thrombosis - delivered with postnatal complication 
L4142 
Postnatal deep vein thrombosis with postnatal complication 
L414z 
Postnatal deep vein thrombosis NOS 
L413. 
Antenatal deep vein thrombosis 
L4130 
Antenatal deep vein thrombosis unspecified 
L4131 
Antenatal deep vein thrombosis - delivered 
L4132 
Antenatal deep vein thrombosis with antenatal complication 
L413z 
Antenatal deep vein thrombosis NOS 
14A81 
H/O: Deep Vein Thrombosis 
ZV128 
[V] Personal history DVT - deep vein thrombosis 
G8020 
Thrombosis of vein of leg 
Read CTV3 Code 
Description 
Xa9Bs 
Deep vein thrombosis 
X205n 
Ileofemoral deep vein thrombosis 
X205m 
Lower venous segment thrombosis 
XaQIV 
Deep venous thrombosis of peroneal vein 
X76Lg 
Phlegmasia alba dolens 
Xa1aj 
Phlegmasia alba dolens - obstetric 
X76Lh 
Phlegmasia caerula dolens 
SP122 
Postoperative deep vein thrombosis 
L413. 
Antenatal deep vein thrombosis 
L4130 
Antenatal deep vein thrombosis unspecified 
L4131 
Antenatal deep vein thrombosis - delivered 
L4132 
Antenatal deep vein thrombosis with antenatal complication 
L413z 
Antenatal deep vein thrombosis NOS 
XE0xL 
Postnatal deep vein thrombosis 
L4140 
Postnatal deep vein thrombosis unspecified 
L4141 
Postnatal deep vein thrombosis - delivered with postnatal complication 
L4142 
Postnatal deep vein thrombosis with postnatal complication 
L414z 
Postnatal deep vein thrombosis NOS 
XaJxo 
Deep vein thrombosis of leg related to intravenous drug use 
XaIIo 
Deep vein thrombosis of leg related to air travel 
Xacve 
Provoked deep vein thrombosis 
Xacvd 
Unprovoked deep vein thrombosis 
XaZ43 
Recurrent deep vein thrombosis 
XaC0s 
Thrombosis of vein of lower limb 
XaBMc 
[V] Personal history DVT - deep vein thrombosis 
14A81 
H/O: Deep Vein Thrombosis 
XaaBG 
On deep vein thrombosis care pathway 
XE0VY 
Deep vein phlebitis and thrombophlebitis of the leg 
G801z 
Deep vein phlebitis and thrombophlebitis of the leg NOS 
X205e 
Deep thrombophlebitis 
Xa205l 
High venous segment venous thrombosis 
G8016 
Thrombophlebitis of femoral vein 
G8017 
Thrombophlebitis of popliteal vein 

G801B 
Thrombophebitis of the leg unspecified 
G802. 
Phlebitis and thrombophlebitis of leg NOS 
Gyu80 
[X] Phlebitis and thrombophlebitis/oth deep vessls/low extremites 
SNOMED CT ID 
Description 
195403006 
(Deep vein phlebitis and thrombophlebitis of the leg) or (deep vein 
thrombosis) 
315760002 
[V] Personal history deep vein thrombosis 
285381000119104 
Acute deep vein thrombosis of bilateral femoral veins 
293491000119107 
Acute deep vein thrombosis of left iliac vein 
15711401000119105 
Acute deep vein thrombosis of left lower limb following procedure 
651000119108 
Acute deep vein thrombosis of lower limb (disorder) 
293481000119109 
Acute deep vein thrombosis of right iliac vein 
15708401000119100 
Acute deep vein thrombosis of right lower limb following procedure 
15708201000119101 
Acute deep vein thrombosis of right upper limb following procedure 
132251000119101 
Acute deep venous thrombosis of popliteal vein (disorder) 
132271000119105 
Acute deep venous thrombosis of thigh (disorder) 
285381000119104 
Acute deep vein thrombosis of bilateral femoral veins (disorder) 
136781000119101 
Acute deep venous thrombosis of lower extremity as complication of 
procedure (disorder) 
132261000119104 
Acute deep venous thrombosis of tibial vein (disorder) 
134961000119104 
Acute deep venous thrombosis of axillary vein (disorder) 
156268003 
Antenatal deep vein thrombosis 
200232006 
Antenatal deep vein thrombosis - delivered 
200234007 
Antenatal deep vein thrombosis NOS 
200231004 
Antenatal deep vein thrombosis unspecified 
200233001 
Antenatal deep vein thrombosis with antenatal complication 
49956009 
Antepartum deep vein thrombosis 
225999004 
At risk of deep vein thrombosis 
293461000119100 
Chronic deep vein thrombosis of left iliac vein (disorder) 
709687000 
Chronic deep vein thrombosis of pelvic vein 
 293451000119102 
Chronic deep vein thrombosis of right iliac vein 
132131000119102 
Chronic deep venous thrombosis of calf (disorder) 
132191000119103 
Chronic deep venous thrombosis of femoral vein (disorder) 
132201000119100 
Chronic deep venous thrombosis of iliofemoral vein (disorder) 
503421000000105 
Deep vein thrombosis enhanced services administration stage 1 service 
level (finding) 
132141000119106 
Chronic deep venous thrombosis of lower extremity (disorder) 
132091000119104 
Chronic deep venous thrombosis of lower limb due to coronary artery 
bypass grafting (disorder) 
132151000119108 
Chronic deep venous thrombosis of popliteal vein (disorder) 
132171000119104 
Chronic deep venous thrombosis of thigh (disorder) 
132221000119109 
Chronic deep venous thrombosis of upper extremity (disorder) 
136751000119108 
Chronic deep venous thrombosis of upper extremity as complication of 
procedure (disorder) 
503451000000100 
Deep vein thrombosis enhanced services administration stage 2 service 
level (finding) 
503481000000106 
Deep vein thrombosis enhanced services administration stage 3 service 
level (finding) 
132551000119104 
Chronic thrombosis of subclavian vein (disorder) 
16750002 
Deep thrombophlebitis  

444325005 
Deep vein thrombosis of bilateral lower extremities (disorder) 
134399007 
Deep vein thrombosis of leg related to air travel 
366830006 
Deep vein thrombosis of leg related to air travel 
366911007 
Deep vein thrombosis of leg related to air travel 
413956008 
Deep vein thrombosis of leg related to intravenous drug use (disorder) 
860699005 
Deep vein thrombosis of lower extremity due to intravenous drug use 
366912000 
Deep vein thrombosis of lower limb 
17920008 
Deep vein thrombosis of portal vein 
14534009 
Deep vein thrombosis of splenic vein 
401186003 
Deep vein thrombosis screening 
155454004 
Deep vein thrombosis-non obst. 
266328001 
Deep vein thrombosis-non obst. 
267361004 
Deep vein thrombosis-obstetric 
128053003 
DVT 
128057002 
DVT - Deep vein thrombosis of lower limb 
404223003 
DVT - Deep vein thrombosis of lower limb 
200235008 
DVT: [postnatal] or [obstetric phlegmasia alba dolens] 
438785004 
Deep venous thrombosis of tibial vein (disorder) 
132161000119105 
Chronic deep venous thrombosis of tibial vein (disorder) 
703277001 
Deep venous thrombosis of femoropopliteal vein (disorder) 
427775006 
Deep venous thrombosis of profunda femoris vein (disorder) 
161508001 
History of deep vein thrombosis 
141911000119100 
History of recurrent deep vein thrombosis 
234044007 
Ileofemoral deep vein thrombosis 
156264001 
Obstetric venous problems (& [deep vein thrombosis] or [varicose vein]) 
(disorder) 
156269006 
Postnatal deep vein thrombosis 
200237000 
Postnatal deep vein thrombosis - delivered with postnatal complication 
200239002 
Postnatal deep vein thrombosis NOS 
200236009 
Postnatal deep vein thrombosis unspecified 
200238005 
Postnatal deep vein thrombosis with postnatal complication 
213220000 
Postoperative deep vein thrombosis 
56272000 
Postpartum deep vein thrombosis 
439993001 
Prevention of deep vein thrombosis (regime/therapy) 
710167004 
Recurrent deep vein thrombosis (disorder) 
431883007 
Referral to deep vein thrombosis clinic (procedure) 
432805000 
Suspected deep vein thrombosis (situation) 
978441000000108 
Provoked deep vein thrombosis (disorder) 
978421000000101 
Unprovoked deep vein thrombosis (disorder) 
869721000000104 
Deep vein thrombosis care pathway (regime/therapy) 
128055005 
Deep venous thrombosis of pelvic vein (disorder) 
443210003 
Deep venous thrombosis of peroneal vein (disorder) 
141911000119100 
History of recurrent deep vein thrombosis (situation) 
15708361000119109 
Acute deep vein thrombosis of left lower limb following coronary artery 
bypass graft (disorder) 
15708241000119104 
Acute deep vein thrombosis of right lower limb following coronary 
artery bypass graft (disorder) 
429098002 
 Thromboembolism of vein (disorder) 

Appendix 4 
Below is a list of the variables to be extracted and utilised for the study 
Variable 
Role 
Data source(s) 
Operational 
definition 
Atopic Dermatitis 
Case definition 
OPCRD 
As defined using the 
codes listed in 
Appendix 1 
Atopic Dermatitis 
severity 
Case definition 
OPCRD 
As defined using the 
codes listed in 
Appendix 1 and the 
approach described in 
section 3.4. 
Atopic Dermatitis 
exclusion conditions 
Case definition 
OPCRD 
As defined using the 
codes listed in 
Appendix 2 
Pulmonary embolism 
(PE) 
Study outcome 
OPCRD 
As defined using the 
codes listed in 
Appendix 3 
Deep vein thrombosis 
(DVT) 
Study outcome 
OPCRD 
As defined using the 
codes listed in 
Appendix 3 
Age 
Baseline characteristic, 
predictor variable 
OPCRD 
Defined as age at the 
start of follow up 
Gender 
Baseline characteristic, 
predictor variable 
OPCRD 
Primary care recorded 
patient gender 
Socioeconomic status 
(SES) 
Baseline characteristic, 
predictor variable 
OPCRD 
Defined using patient 
index of multiple 
deprivation quintile 
Ethnicity 
Baseline characteristic, 
predictor variable 
OPCRD 
Defined using office of 
national statistics 
census categories using 
clinically coded 
ethnicity data 
Smoking status 
Baseline characteristic, 
predictor variable 
OPCRD 
Using most recent 
clinically recorded 
smoking status 
information 
Alcohol use 
Baseline characteristic, 
predictor variable 
OPCRD 
Using most recent 
clinically recorded 

alcohol use status 
information 
Body mass index (BMI) 
Baseline characteristic, 
predictor variable 
OPCRD 
Defined using most 
recent clinically 
recorded BMI 
information 
Death 
Censoring event 
OPCRD 
Identified from coding 
in the clinical record 
Deregistration from GP 
Censoring event 
OPCRD 
Identified from coding 
in the clinical record 
Atrial fibrillation 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Angina 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Myocardial infarction 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Congestive heart failure 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Stroke 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Diabetes type 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Hyperlipidaemia 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Hypertension 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Chronic kidney disease 
stages 3-5 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
and lab test results   
Chronic obstructive 
pulmonary disease,  
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Asthma 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Chronic liver disease 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Dementia 
Baseline characteristic, 
predictor variable 
OPCRD 
Identified using clinical 
codes for the condition 
Immunotherapy use 
Potential predictor 
variable 
OPCRD 
Identified using 
prescription records for 
immunotherapy 

Phototherapy 
treatment 
Potential predictor 
variable 
OPCRD 
Identified using 
prescription records 
and clinical codes for 
phototherapy