The UK Biobank has made general practitioner (GP) data (censoring date 2016–2017) available for approximately 45% of the cohort, whilst hospital inpatient and death registry (referred to as “HES/Death”) data are available cohort-wide through 2018–2022 depending on whether the data comes from England, Wales or Scotland. We assessed the importance of case ascertainment via different data sources in UKB for three diseases that are usually first diagnosed in primary care: Parkinson’s disease (PD), type 2 diabetes (T2D), and all-cause dementia. Including GP data at least doubled the number of incident cases in the subset of the cohort with primary care data (e.g. from 619 to 1390 for dementia). Among the 786 dementia cases that were only captured in the GP data before the GP censoring date, only 421 (54%) were subsequently recorded in HES. Therefore, estimates of the absolute incidence or risk-stratified incidence are misleadingly low when based only on the HES/Death data. For incident cases present in both HES/Death and GP data during the full follow-up period (i.e. until the HES censoring date), the median time difference between an incident diagnosis of dementia being recorded in GP and HES/Death was 2.25 years (i.e. recorded 2.25 years earlier in the GP records). Similar lag periods were also observed for PD (median 2.31 years earlier) and T2D (median 2.82 years earlier). For participants with an incident GP diagnosis, only 65.6% of dementia cases, 69.0% of PD cases, and 58.5% of T2D cases had their diagnosis recorded in HES/Death within 7 years since GP diagnosis. The effect estimates (hazard ratios, HR) of established risk factors for the three health outcomes mostly remain in the same direction and with a similar strength of association when cases are ascertained either using HES only or further adding GP data. The confidence intervals of the HR became narrower when adding GP data, due to the increased statistical power from the additional cases. In conclusion, it is desirable to extend both the coverage and follow-up period of GP data to allow researchers to maximise case ascertainment of chronic health conditions in the UK.

英国生物银行已为大约 45% 的队列提供了全科医生 (GP) 数据（审查日期为 2016-2017 年），而医院住院患者和死亡登记（称为“HES/死亡”）数据可通过以下方式获得整个队列的数据： 2018-2022 年，取决于数据来自英格兰、威尔士还是苏格兰。我们通过 UKB 的不同数据源评估了针对通常在初级保健中首先诊断出的三种疾病的病例确定的重要性：帕金森病 (PD)、2 型糖尿病 (T2D) 和全因痴呆。包含全科医生数据至少使具有初级保健数据的队列子集中的事件病例数增加了一倍（例如，痴呆症从 619 例增加到 1390 例）。在 GP 审查日期之前仅在 GP 数据中捕获的 786 例痴呆病例中，只有 421 例 (54%) 随后记录在 HES 中。因此，仅基于 HES/死亡数据时，绝对发病率或风险分层发病率的估计值较低，具有误导性。对于在整个随访期间（即直到 HES 审查日期）同时出现在 HES/死亡和 GP 数据中的事件病例，GP 中记录的痴呆事件诊断与 HES/死亡之间的中位时间差为 2.25 年（即在 GP 记录中记录为 2.25 年前）。 PD（中位数提前 2.31 年）和 T2D（中位数提前 2.82 年）也观察到了类似的滞后期。对于接受 GP 诊断的参与者，只有 65.6% 的痴呆病例、69.0% 的 PD 病例和 58.5% 的 T2D 病例在 GP 诊断后 7 年内将其诊断记录在 HES/死亡中。当仅使用 HES 或进一步添加 GP 数据来确定病例时，三种健康结果的既定风险因素的效应估计（风险比，HR）大多保持相同的方向，并且具有相似的关联强度。添加 GP 数据时，HR 的置信区间变得更窄，因为附加病例的统计功效增强。总之，希望扩大全科医生数据的覆盖范围和随访期，以便研究人员能够最大限度地确定英国慢性健康状况的病例。