Supplementary Material for: Implications of the Use of Algorithmic Diagnoses or Medicare Claims to Ascertain Dementia

<b><i>Introduction:</i></b> Formal dementia ascertainment with research criteria is resource-intensive, prompting the growing use of alternative approaches. Our objective was to illustrate the potential bias and implications for study conclusions introduced through the use of alternate dementia ascertainment approaches. <b><i>Methods:</i></b> We compared dementia prevalence and risk factor associations obtained using criterion-standard dementia diagnoses to those obtained using algorithmic or Medicare-based dementia ascertainment in participants of the baseline visit of the Aging, Demographics, and Memory Study (ADAMS), a Health and Retirement Study (HRS) sub-study. <b><i>Results:</i></b> Estimates of dementia prevalence derived using algorithmic or Medicare-based ascertainment differ substantially from those obtained using criterion-standard ascertainment. Use of algorithmic or Medicare-based dementia ascertainment can, but does not always, lead to risk factor associations that substantially differ from those obtained using criterion-standard ascertainment. <b><i>Discussion/Conclusions:</i></b> Absolute estimates of dementia prevalence should rely on samples with formal dementia ascertainment. The use of multiple algorithms is recommended for risk factor studies when formal dementia ascertainment is not available.

**引言：** 采用研究标准开展正规痴呆确认工作属于资源密集型任务，这促使替代确认方法的应用日益增多。本研究旨在阐明采用替代痴呆确认方法时可能引入的偏倚及其对研究结论的影响。
**方法：** 本研究以健康与退休研究（Health and Retirement Study, HRS）的子研究——衰老、人口统计学与记忆研究（Aging, Demographics, and Memory Study, ADAMS）的基线访视参与者为对象，将采用标准研究诊断标准确诊的痴呆患病率及危险因素关联结果，与采用算法或基于医疗保险（Medicare）的痴呆确认方法所得结果进行了对比。
**结果：** 采用算法或基于医疗保险的确认方法得出的痴呆患病率估算值，与采用标准研究确诊方法所得结果存在显著差异。采用算法或基于医疗保险的痴呆确认方法，可能（但并非总是）会得出与标准研究确诊方法所得结果显著不同的危险因素关联分析结果。
**讨论与结论：** 痴呆患病率的绝对估算值应基于采用正规痴呆确认方法的研究样本。当无法开展正规痴呆确认工作时，危险因素相关研究建议采用多种算法进行痴呆确认。