Evidence map›Paper›PMID 42095006›Full record

ArticleLearning health systems2026

Assessing the Importance of Variation in Diagnostic Coding Among the Three Countries in the UK Biobank.

Lei Clifton, Wenyu Liu, Jennifer A Collister, Thomas J Littlejohns, Raphael R Goldacre, Naomi Allen, David J Hunter

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Article in Learning health systems, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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2 · The registry

The trial behind it

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

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5 · Who and what money

Authors and funding

7 authors.

Lei CliftonNuffield Department of Primary Care Health Sciences University of Oxford Oxford UK.ORCID https://orcid.org/0000-0001-5595-8468
Wenyu LiuNuffield Department of Population Health University of Oxford Oxford UK.
Jennifer A CollisterNuffield Department of Population Health University of Oxford Oxford UK.
Thomas J LittlejohnsNuffield Department of Population Health University of Oxford Oxford UK.
Raphael R GoldacreNuffield Department of Population Health University of Oxford Oxford UK.
Naomi AllenNuffield Department of Population Health University of Oxford Oxford UK.
David J HunterNuffield Department of Population Health University of Oxford Oxford UK.

Funding

Wellcome Trust
6 · The paper itself

Abstract

Background: The UK Biobank (UKB) study has linked hospital inpatient data collected from England, Scotland, and Wales, which use different clinical coding systems to record health outcomes. Scotland records up to 6 different diagnostic codes for one inpatient episode, compared with up to 20 in England and 14 in Wales. We assessed the relationship of the variations in diagnostic coding among countries on observed disease incidence rates. Methods: We examined the number of diagnoses coded by each country, and then compared the incidence of three diseases between countries: Parkinson's disease (PD), type 2 diabetes (T2D), and dementia. We constructed Cox models for each disease, adjusting for "country." Results: Compared with England, Scotland appears to have the lowest risk (hazard ratio, HR) for all three diseases: HR [95% CI] = 0.62 [0.54, 0.72] for PD, 0.49 [0.45, 0.54] for T2D, and 0.88 [0.78, 0.99] for dementia. Conclusions: The observed incidence of these diseases and the estimated effect of "country" in Cox models are likely influenced by the clinical coding variations among countries. Researchers need to be aware of this and account for these variations in their analyses.

Indexed as

country variationdementiadiagnostic codingParkinson's disease (PD)type 2 diabetes (T2D)UK Biobank (UKB)

Identifiers

PMID42095006
PMCPMC13142220

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