Department of Psychiatry, University of Cambridge, Cambridge, Cambridgeshire, UK
MRC Epidemiology Unit, Cambridge, Cambridgeshire, UK.
BMJ Open. 2022 Jun 15;12(6):e060931. doi: 10.1136/bmjopen-2022-060931.
To evaluate the characteristics of individuals recorded as having a dementia diagnosis in different routinely collected records and to examine the extent of overlap of dementia coding across data sources. Also, to present comparisons of secondary and primary care records providing value for researchers using routinely collected records for dementia outcome capture.
A prospective cohort study.
A cohort of 25 639 men and women in Norfolk, aged 40-79 years at recruitment (1993-1997) followed until 2018 linked to routinely collected to identify dementia cases. Data sources include mortality from death certification and National Health Service (NHS) hospital or secondary care records. Primary care records for a subset of the cohort were also reviewed.
Diagnosis of dementia (any-cause).
Over 2000 participants (n=2635 individuals) were found to have a dementia diagnosis recorded in one or more of the data sources examined. Limited concordance was observed across the secondary care data sources. We also observed discrepancies with primary care records for the subset and report on potential linkage-related selection bias.
Use of different types of record linkage from varying parts of the UK's health system reveals differences in recorded dementia diagnosis, indicating that dementia can be identified to varying extents in different parts of the NHS system. However, there is considerable variation, and limited overlap in those identified. We present potential selection biases that might occur depending on whether cause of death, or primary and secondary care data sources are used. With the expansion of using routinely collected health data, researchers must be aware of these potential biases and inaccuracies, reporting carefully on the likely extent of limitations and challenges of the data sources they use.
评估不同常规收集记录中记录为痴呆诊断的个体特征，并检查痴呆编码在数据源之间的重叠程度。此外，还将展示二级和初级保健记录之间的比较，为使用常规收集记录进行痴呆结果捕获的研究人员提供价值。
前瞻性队列研究。
在诺福克的一个队列中，共有 25639 名 40-79 岁的男性和女性在招募时（1993-1997 年）进行随访，直至 2018 年与常规收集数据相关联以确定痴呆病例。数据来源包括死亡证明和国家卫生服务（NHS）医院或二级保健记录中的死亡率。还对队列的一部分进行了初级保健记录审查。
痴呆（任何原因）诊断。
在检查的多个数据源中，有超过 2000 名参与者（n=2635 人）被发现记录了一个或多个痴呆诊断。在二级保健数据源中观察到一致性有限。我们还观察到与部分初级保健记录的差异，并报告了潜在的与链接相关的选择偏差。
使用来自英国卫生系统不同部分的不同类型的记录链接揭示了记录痴呆诊断的差异，表明在 NHS 系统的不同部分可以在不同程度上识别痴呆。然而，存在相当大的差异，并且在确定的人群中重叠有限。我们提出了可能出现的潜在选择偏差，这取决于是否使用死因或初级和二级保健数据源。随着常规收集健康数据的扩展，研究人员必须意识到这些潜在的偏差和不准确之处，并仔细报告他们使用的数据源可能存在的局限性和挑战的程度。
