bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trends in systematic recording errors of blood pressure and association with outcomes in Canadian and UK primary care data: a retrospective observational study
Authors: Kalia Sumeet , Greiver Michelle 
Published: September 2018

IntroductionEnd digit preference (EDP) or systematic bias in the recording of blood pressure (BP) measurement is prevalent in primary care: up to 60% of BP readings end in zero. High blood pressure (BP) is a leading cause of increased morbidity in adults and errors in measurement may contribute to increased rate of adverse cardiovascular outcomes.
Objectives and ApproachWe studied EDP trends, uptake of Automated Office BP (AOBP) measurement, and cardiovascular outcomes in the UK and Canada.This is a retrospective observational study using routinely collected Electronic Medical Record data for patients age 18 or more.
We used bootstrap method to estimate the odds ratios where logistic regression was fitted on one thousand independently sampled replicates of the CPCSSN and RCGP datasets. We implemented the unsupervised algorithm of k-nearest neighbor across all sites to find the optimal decision boundary to classify the sites into the three categories: (1) strong EDP; (2) some EDP; (3) no EDP.
ResultsThe mean rate of end digit zero for both systolic and diastolic BP decreased from 26.6% in 2006 to 15.4% in 2015 in Canada and from 24.2% in 2001 to 17.3% in 2015 in the U.K. There was a gradual decline in EDP in the three years following the purchase of an AOBP machine. Sites categorized as having high levels of EDP had lower mean sBP levels than sites with potentially no EDP in both Canada and UK. Patients in sites with high levels of EDP had higher yearly prevalence of stroke (Standardized morbidity ration or SMR 1.11), myocardial infarcts (SMR 1.15), and angina (SMR 1.27) than patients in sites with no EDP.
Conclusion/ImplicationsThere is systematic recording errors including rounding down of BP readings associated with higher rates of EDP and presumably more use of manual BP measurement. Higher rates of EDP were associated with greater prevalence of adverse cardiovascular outcomes. Consideration should be given to using AOBP machines in primary care.
Scalable Secure Privacy-Preserving Record Linkage (PPRL) Methods Using Cloud-based Infrastructure
Authors: Ong Toan , Lazrig Ibrahim , Ray Indrajit , Ray Indrakshi , Kahn Michael 
Published: September 2018

IntroductionBloom Filters (BFs) are a scalable solution for probabilistic privacy-preserving record linkage but BFs can be compromised. Yao’s garbled circuits (GCs) can perform secure multi-party computation to compute the similarity of two BFs without a trusted third party. The major drawback of using BFs and GCs together is poor efficiency.
Objectives and ApproachWe evaluated the feasibility of BFs+GCs using high capacity compute engines and implementing a novel parallel processing framework in Google Cloud Compute Engines (GCCE). In the Yao’s two-party secure computation protocol, one party serves as the generator and the other party serves as the evaluator. To link data in parallel, records from both parties are divided into chunks. Linkage between every two chunks in the same block is processed by a thread. The number of threads for linkage depends on available computing resources. We tested the parallelized process in various scenarios with variations in hardware and software configurations.
ResultsTwo synthetic datasets with 10K records were linked using BFs+GCs on 12 different software and hardware configurations which varied by: number of CPU cores (4 to 32), memory size (15GB – 28.8GB), number of threads (6-41), and chunk size (50-200 records). The minimum configuration (4 cores; 15GB memory) took 8,062.4s to complete whereas the maximum configuration (32 cores; 28.8GB memory) took 1,454.1s. Increasing the number of threads or changing the chunk size without providing more CPU cores and memory did not improve the efficiency. Efficiency is improved on average by 39.81% when the number of cores and memory on the both sides are doubled. The CPU utilization is maximized (near 100% on both sides) when the computing power of the generator is double the evaluator.
Conclusion/ImplicationsThe PPRL runtime of BFs+GCs was greatly improved using parallel processing in a cloud-based infrastructure. A cluster of GCCEs could be leveraged to reduce the runtime of data linkage operations even further. Scalable cloud-based infrastructures can overcome the trade-off between security and efficiency, allowing computationally complex methods to be implemented.
Using Large Data to Present Uncertainty for Risk Prediction in the Era of Precision Medicine: The RESPECT Algorithm for Predicted Death at End-of-Life
Authors: Spruin Sarah , Hsu Amy , Talarico Robert , Sequeira Yulric , Taljaard Monica , Bennett Carol , Tanuseputro Peter , Manuel Doug 
Published: September 2018

IntroductionIn Ontario, only 52% of people received palliative care in their last year of life, with only 20\% of those receiving it at home, which can improve the dying experience. Existing algorithms identifying people at end-of-life can potentially improve access to palliative care but are difficult for patients to understand.
Objectives and ApproachTo predict and communicate risk of death for community dwelling older adults using a pre-specified and published approach (Trial registration NCT02779309). All assessments from community-dwelling Ontarians (N = 488,636) who received at least one home care assessment from the residential assessment instrument – home care (RAI HC) from 2007 to 2013 (N=1,331,273) were included. The algorithm used a two-step approach by rank ordering participants into 61 groups based on six-month probability of death (from Cox-proportional hazard models) and generated Kaplan-Meier five-year survival curves for each group. Median Survival time is reported with uncertainties expressed with 25th to 75th percentiles.
ResultsThe median predicted probability of death within six-months was 0.1095 (0.1093-0.1097, 95% CI). Risk varied among the 61 groups from 0.0158 (0.0158-0.0159) to 0.9820 (0.9810-0.9830). Median observed survival time varied from 27 days (10 to 81 days, 25th and 75th percentile) in the highest risk group to 10 years (3655 days (2111 to >3655 days)) in the lowest risk group. Discrimination and calibration were satisfactory between the derivation (2007-2012 assessments) and validation (2013 assessments) cohorts, with a C statistics of 0.77 and discrimination plot intercept 0.094, slope 0.914. The Kaplan-Meier five-year survival curves for each of the 61 groups will be visually represented in six different ways displaying the risk and uncertainty, and can be altered to yield information of interest specific to each patient/caregiver.
Conclusion/ImplicationsRESPECT is adaptive and personalized, with instantaneous feedback as the user provides a response to each question. We will present RESPECT’s development and implementation processes and set up an interactive presentation of the calculator, demonstrating RESPECT’s ability to deliver patient-comprehensible end-of-life prognoses with uncertainty to patients and their caregivers.
Creating the Framework for Cross-Sector Health Analysis for Local Communities
Authors: Richards Heather , Varas Kim , Magnus Samantha , Oh Jinhwa , Voggenreiter Christine 
Published: September 2018

IntroductionA newly developed BC Ministry of Health geography classification has enabled a standardized approach for community-level analysis of health needs and service provision. An innovative methodology was developed and applied to health administrative data, creating more opportunities to identify variations in health status and utilization across the health system.
Objectives and ApproachTwo design principles informed the development of the new geographies. Firstly, they reflect where people live and the communities with which they identify, and secondly, they will assist with identifying where health services are needed for local populations. The objective was to provide the Ministry and health authorities with a framework to identify and work towards providing the optimal delivery of services at the local level. A working group was established for this project and included representatives from the Ministry, each regional health authority, Provincial Health Services Authority, First Nations Health Authority, and BC Stats.
ResultsThe building block for the geography classification is the Census Dissemination Block, the lowest unit of geography available in the Standard Geography Classification maintained by Statistics Canada. The geographies were assigned urban-rural designations based on an algorithm that considered the presence of a population centre, the size of the population centre, and the proportion of the population living in it, among other aspects. One of the main goals of the urban-rural designations was to provide meaningful peer groups for cross-jurisdictional studies.
The project also reengineered the methods to geocode addresses to improve accuracy to use street addresses (over past method that used postal codes) so that assignment to Census Dissemination Block would be precise.
The end result was 218 community geographies with urban-rural designations.
Conclusion/ImplicationsThis geography standard allows health system stakeholders to better understand of geographic variation in utilization and access to health care. The ability to link and share information to profile community health between health administrative data and Census data available from Statistics Canada is better due to improved geocoding of addresses.
Life expectancy and health-adjusted life expectancy are decreased in people living with inflammatory bowel disease: a population-based matched cohort study
Authors: Kuenzig Ellen , Manuel Doug , Donelle Jessy , Benchimol Eric 
Published: September 2018

IntroductionInflammatory bowel disease (IBD) is a chronic immune-mediated disease of the gastrointestinal tract. Significant improvements in treatments for IBD have occurred in the past two decades. However, the benefits of new treatments on mortality is uncertain and no prior study has evaluated the life expectancy (LE) of patients with IBD.
Objectives and ApproachWe determined trends in the LE and health-adjusted life expectancy (HALE) in IBD. The Ontario Crohn’s and Colitis Cohort includes all patients in Ontario with IBD, identified from health administrative data using a previously validated algorithm. Cases were matched to five controls based on age, sex, rural/urban, and mean neighbourhood income quintile. Period life tables were used to calculate LE on July 1, 1996, 2000, and 2008. The Canadian National Population Health Survey (1996/97) and Canadian Community Health Survey (Cycles 1.1 and 2009/10) were used to estimate health utility index (HUI3). HALE was estimated using HUI3-weighted disability-free years lived.
ResultsLE increased from 75.5 years (y) in 1996 to 78.0y in 2008 among women with IBD (∆2.5y, 95%CI 0.8 to 4.1) and from 72.2y in 1996 to 75.1y in 2008 among men with IBD (∆2.9y, 95%CI 1.8 to 4.0). HALE decreased among men with IBD (∆3.9y, 95%CI 1.2 to 6.6; 1996: 67.0y; 2008: 63.1y) but was stable among women with IBD (∆2.0y, 95%CI -1.6 to 5.7; 1996: 62.3y; 2008: 64.3y) and female controls (∆-0.4y, 95%CI -2.3 to 1.5; 1996: 74.3y; 2008: 73.9y) and male controls (∆0.2y, 95%CI -1.7 to 2.2; 1996: 69.6y; 2008: 69.8y). LE and HALE in both men and women with IBD were significantly decreased compared to controls (LE: women ∆6-8y, men ∆5y; HALE: women ∆10-14y, men ∆3-7y).
Conclusion/ImplicationsAlthough patients with IBD experienced increases in LE at a pace similar to those without IBD, the gap in LE between cases and controls remains significant. Increases in LE have not been accompanied by increases in HALE. Treatments that increase both LE and HALE in patients with IBD are needed.
Governance Challenges to Promoting Data Readiness and Data Linkage for Not-for-Profit Organizational Service Data
Authors: Manhas Kiran Pohar , Lau Jason , Cui Xinjie 
Published: September 2018

IntroductionData collected by myriad not-for-profit (NFPs) agencies while providing social services represent a significant untapped source of intelligence. While much research has been conducted on the governance and capacity to share administrative and research data, little work has been done in the area of NFP data sources.
Objectives and ApproachSix NFP agencies in Calgary participated in a data sharing project to measure various aspects of poverty. This collaboration required understanding the legal, ethical, policy and data challenges to working with data collected in the NFP sector. This case study will expose (a) the legal analysis on legal and governance issues for, and obligations of, NFPs when aiming to share and re-use information beyond service delivery in Alberta, Canada; and (b) the practical and policy challenges faced by the NFPs and repository. The legal analysis involved a systematic search of academic and grey literature; relevant legislation and case-law (especially privacy law).
ResultsThe legal analysis demonstrated three key things. First, in many circumstances an NFP is not held to any information-handling legal obligations. This does not absolve NFPs from social privacy expectations, especially involving vulnerable populations. Second, privacy best practices are available to NFPs from other more-regulated sectors and from NFP sector standards. The trifecta of purpose, reasonableness and minimal extent are critical. Third, adhering to privacy best practices would not be overly costly, more efficient, and less risky of negative publicity and lost public trust from privacy complaints. These findings informed the NFP data sharing project. The six participant NFPs varied greatly in their approach to consent, governance and information-handling, which affected their data-readiness for cross-organizational data linkage and analysis.
Conclusion/ImplicationsUnlike government, most NFPs have limited experience with data linkage. This paper informs ethical approaches to include NFP data in broad cross-sector data linkage. Appropriate data governance is imperative for data sharing amongst NFPs, researchers and public organizations, which promotes community service delivery, evaluation and improvements to benefit vulnerable families.
Childhood Mental Disorders and Subsequent Adverse Outcomes in Early Adulthood: A Population-Based Longitudinal Study
Authors: Chartier Mariette , Bolton James , Ekuma Oke , Mota Natalie , Hensel Jennifer , MacWilliam Leonard , Nie Yao , McDougall Chelsey 
Published: September 2018

IntroductionThe relationship between childhood/adolescent mental disorders and adult outcomes has been studied using surveys and clinical samples. These studies are prone to selection, recall and self-reporting biases. No previous studies have used population-based administrative databases linking individual-level data that could address these biases and further elucidate this relationship.
Objectives and ApproachUsing de-identified administrative databases housed at the Manitoba Centre for Health Policy, we aimed to determine whether people diagnosed with mental disorders in childhood/adolescence, compared to those without, were at higher risk of early adverse adult outcomes. We created a birth cohort of 60,838 residents of Manitoba, Canada, born from fiscal years 1980/81 to 1984/85 and followed them to the end of study period in 2014/15. Through a scrambled health identifier, health, education, social services and justice system data were linked at an individual level. Survival analysis was used to test for differences controlling for key childhood covariates.
ResultsWe found that 16.5% of the cohort had a diagnosed mental disorder at some point in their childhood/adolescence. Having a diagnosed mental disorder in childhood/adolescence increased the risk of being diagnosed with the same disorder in early adulthood (at age 30 to 34 years old). It also increased the risk of suicidal death (hazard ratio (HR): 2.41), suicide attempts (HR: 3.05), public housing use (HR: 1.44), income assistance use (HR: 2.07), criminal accusation (HR:1.53), and criminal victimization (HR:1.54) in adulthood. Similarly, but to a greater extent, suicide attempts in adolescence increased the risk of suicidal death (HR: 3.65), suicide attempts (HR: 5.68), public housing use (HR: 1.64), income assistance use (HR: 1.68), criminal accusation (HR: 2.18), or criminal victimization (HR: 2.43) in adulthood.
Conclusion/ImplicationsYoung people’s mental health has significant influence on their health and well-being trajectories into adulthood. This knowledge could directly inform policy and practice to provide better population-based mental health promotion, prevention and early interventions for children/adolescents with mental disorders and subsequently prevent adverse adult outcomes in the future.
Privacy, Ethics and Information Sharing of New Zealand’s Integrated Data Infrastructure (IDI): A discussion of the issues, challenges and opportunities
Authors: Atkinson June 
Published: September 2018

IntroductionNew Zealand’s (NZ) Integrated Data Infrastructure (IDI) has rapidly expanded since our 2016 IPDLN conference update. Researchers have available a wide range of administrative and survey data. Even major earthquake damage to a Statistics NZ building in late 2016 has not halted progress with expanding the IDI and its usage.
Objectives and ApproachTo provide an update on the current state of the IDI and its use by the NZ research community.
To highlight some key areas that need further discussion because of the IDI’s rapid growth, especially concerning :

Privacy, regulation and governance: how to make progress within appropriate regulatory constraints, especially around maintaining confidentiality, data sovereignty, data ethics and data security.
Capacity building: what are the best ways to build multidisciplinary skills for new IDI users, share code and knowledge and what types of networking options work best?
Cross-sectoral data linkage: to maximise the value of the IDI.

ResultsIn the last two years there has been a rapid expansion of external datalabs with access to the IDI (now around 33) and with the number of researchers using these datalabs (around 650). This has resulted in many useful research outputs; but it has also highlighted some areas that need more consideration including:

Data sovereignty: NZ needs to ensure a strong role of Māori (Indigenous NZers) in data governance to ensure that IDI data are used to maximise reduction in health and social inequalities.
Options for assisting new IDI users and exploring the best ways of sharing code, knowledge and networking.
To maximise value there needs more focus on use of cross-sectoral data linkage (to better understand the impact of social determinants on long-term health).

Conclusion/ImplicationsThere has been rapid expansion of the scope and use of the IDI in New Zealand. But to ensure the continuation of the success to date, even more attention needs to be paid to such issues as data governance and data protection.
Developing a new metric to capture continuity of primary care: The application of propensity score methods and threshold effects models using linked administrative data
Authors: Ha Ninh Thi , Harris Mark , Moorin Rachael 
Published: September 2018

IntroductionEnhancement of primary care has been focused in many countries to make the healthcare system more productive in response to increasing burden of chronic conditions. Despite tremendous growth of linked administrative data, methods to use the administrative data to evaluate and improve the performance of primary care have been limited.
Objectives and ApproachThe study uses linked administrative data of people diagnosed with diabetes to develop and test a new metric that will facilitate better measurement of continuity of primary care named “cover metric”. Cover adds a time element into our previously developed regularity score compartmentalising days between GP visits into within and outside of a particular time period determined using threshold models that are either associated with a reduced (within) or increased (outside) the risk of hospitalisation. The number of days within is then summed over an ascertainment period of 365 days (calendar year) and an annual proportion calculated for each person.
ResultsThree cohorts of people with diabetes were identified based on complication severity index at the baseline year. The risk of hospitalisations among people with diabetes can vary across a range of primary care usage and other covariates. The use of propensity scores allowed us to assess the balance of observed covariates across different levels of primary care usage and to isolate the effect of primary care usage on the risk of hospitalisation from the covariates. The threshold effects models examined how the risk of hospitalisation varied with the length of time following a primary care visit to indicate the time interval which the risk of hospitalisation was lowest. The time interval was then used to construct the cover metric for each defined diabetes severity cohort.
Conclusion/ImplicationsThe new cover metric will significantly contribute to the sparsely available methods for the analysis of linked administrative data in evaluating continuity of primary care. Combination of propensity score and threshold effect models are showcased as useful analytic approaches in the examination of the relationship between primary care and hospitalisations.
Validation of mechanical ventilation coding in hospital discharge abstracts: a population data linkage study
Authors: Nie Yao , Olafson Kendiss , Sareen Jitender , Yogendran Marina 
Published: September 2018

IntroductionMechanical ventilation (MV) is an important intervention used in critically ill patients. Accurately identifying MV use in Hospital Discharge Abstracts will be extremely useful in population-based research. Although Canadian Institute for Health Information collects information on MV for all hospitalization, its validity in intensive care unit (ICU) patients is unknown.
Objectives and ApproachWe validated MV use within ICU patients in Hospital Discharge Abstracts. Winnipeg Regional Health Authority (WRHA) ICU database prospectively collects use of MV by trained nurses. All patients admitted to a WRHA ICU (82 beds) between April 1, 2000 and March 31, 2012 were identified in Hospital Discharge Abstracts. MV was identified in Hospital Discharge Abstracts through International Classification of Diseases (ICD-9-CM), prior to 2004, while Canadian Classification of Health Interventions (CCI) were used 2004 onwards. Agreement between the WRHA database (gold standard) and Hospital Discharge Abstracts for invasive ventilation, non-invasive ventilation or neither was calculated at ICU encounter level.
ResultsThere were 54,680 WRHA ICU admission during the study period. The linking of these two sources was highly successful with accurate identification exceeding 99%. There were 26,083 mechanical ventilations (25,387 invasive; 696 non-invasive) from the Hospital Discharge Abstracts and 30,455 (28,315 invasive; 4,554 non-invasive) from the CIC data. Hospital Discharge Abstracts had a sensitivity of 82.8%, specificity of 96.4%, Positive Predictive Value (PPV) of 96.7%, and Negative Predictive Value (NPV) of 81.7% for identifying mechanical ventilation. For invasive ventilation, Sensitivity was 85.5%, Specificity was 95.6%, PPV was 95.4% and NPV was 86.0%. Validation of non-invasive ventilation was poor in sensitivity (9.38%) and PPV (61.35%): with specificity 99.5% and NPV 92.36%.
Conclusion/ImplicationsHospital Abstracts data are a good source to identity mechanically ventilated patients for ICU containing hospital stays especially invasive mechanical ventilations. Future research needs to explore the poor agreement with non-invasive mechanical ventilation.