ArticleBMJ open2017
Quality of recording of diabetes in the UK: how does the GP's method of coding clinical data affect incidence estimates? Cross-sectional study using the CPRD database.
Article in BMJ open, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 40 papers, 3 of them syntheses that pooled it.
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Who cites it
40 citing papers in PubMed, 3 syntheses or guidelines pooled it.
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- Understanding variations in reported epidemiology of major lower extremity amputation in the UK: a systematic review.BMJ open · 2021Pooled it
- Using general practice data for chronic disease prevalence: the impact of record linkage on estimation accuracy.BMC medical informatics and decision making · 2025Article
- Obstructive Sleep Apnoea and Risk of Fragility Fracture in Patients With Type 2 Diabetes: A Population-Based Retrospective Cohort Study.Endocrinology, diabetes & metabolism · 2025Article
- A Composite Indicator for Primary Diabetes Care: A Cross-Sectional Study in Hungary.Healthcare (Basel, Switzerland) · 2025Article
- Investigating misclassification of type 1 diabetes in a population-based cohort of British Pakistanis and Bangladeshis using polygenic risk scores.Scientific reports · 2025Article
- Optimal risk assessment intervals for primary prevention of cardiovascular disease: a population-based two-stage landmarking study.BMJ public health · 2025Article
- The impact of COVID-19 on medication reviews in English primary care. An OpenSAFELY-TPP analysis of 20 million adult electronic health records.British journal of clinical pharmacology · 2024Article
- Identifying subtypes of type 2 diabetes mellitus with machine learning: development, internal validation, prognostic validation and medication burden in linked electronic health records in 420 448 individuals.BMJ open diabetes research & care · 2024Article
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- Inequalities in cancer mortality trends in people with type 2 diabetes: 20 year population-based study in England.Diabetologia · 2023Article
- All-cause and cardiorenal mortality in 6 million adults with and without type 2 diabetes: A comparative, trend analysis in Canada, Spain, and the UK.Diabetes, obesity & metabolism · 2023Article
- Prioritising cardiovascular disease risk assessment to high risk individuals based on primary care records.PloS one · 2023Article
- Incremental value of risk factor variability for cardiovascular risk prediction in individuals with type 2 diabetes: results from UK primary care electronic health records.International journal of epidemiology · 2022Article
- Increased risk of type 3c diabetes mellitus after acute pancreatitis warrants a personalized approach including diabetes screening.BJS open · 2022Article
- Natural history and burden of Huntington's disease in the UK: A population-based cohort study.European journal of neurology · 2022Article
- Clinical code usage in UK general practice: a cohort study exploring 18 conditions over 14 years.BMJ open · 2022Article
- Validation of Diagnostic Coding for Diabetes Mellitus in Hospitalized Patients.Endocrine practice : official journal of the American College of Endocrinology and the American Association of Clinical Endocrinologists · 2022Article
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Authors and funding
6 authors.
Funding
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Abstract
objectiveTo assess the effect of coding quality on estimates of the incidence of diabetes in the UK between 1995 and 2014.
designA cross-sectional analysis examining diabetes coding from 1995 to 2014 and how the choice of codes (diagnosis codes vs codes which suggest diagnosis) and quality of coding affect estimated incidence.
settingRoutine primary care data from 684 practices contributing to the UK Clinical Practice Research Datalink (data contributed from Vision (INPS) practices).
main outcome measureIncidence rates of diabetes and how they are affected by (1) GP coding and (2) excluding 'poor' quality practices with at least 10% incident patients inaccurately coded between 2004 and 2014.
resultsIncidence rates and accuracy of coding varied widely between practices and the trends differed according to selected category of code. If diagnosis codes were used, the incidence of type 2 increased sharply until 2004 (when the UK Quality Outcomes Framework was introduced), and then flattened off, until 2009, after which they decreased. If non-diagnosis codes were included, the numbers continued to increase until 2012. Although coding quality improved over time, 15% of the 666 practices that contributed data between 2004 and 2014 were labelled 'poor' quality. When these practices were dropped from the analyses, the downward trend in the incidence of type 2 after 2009 became less marked and incidence rates were higher.
conclusionsIn contrast to some previous reports, diabetes incidence (based on diagnostic codes) appears not to have increased since 2004 in the UK. Choice of codes can make a significant difference to incidence estimates, as can quality of recording. Codes and data quality should be checked when assessing incidence rates using GP data.
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