Nelson L M, Longstreth W T, Koepsell T D, Checkoway H, van Belle G
Neuroepidemiology Group, University of Washington, Seattle.
Epidemiology. 1994 Mar;5(2):204-17. doi: 10.1097/00001648-199403000-00011.
To evaluate the quality of exposure data provided by proxy respondents, we used a dual interview protocol in a case-control study of subarachnoid hemorrhage. All control subjects and their proxy respondents were interviewed (N = 283 control-proxy pairs), as were the cases who were able to provide their own information and their proxy respondents (N = 68 case-proxy pairs). The reliability of proxy-derived data was excellent for demographic and body habitus measures (kappa or intraclass correlation range = 0.86-0.99), and all aspects of cigarette smoking history (range = 0.79-0.93). Proxy reliability was somewhat lower for questions regarding medications and hormone preparations (range = 0.55-0.88), alcohol consumption (range = 0.52-0.82), and recreational physical activity (range = 0.55-0.67). Proxy reliability varied according to the relationship of the proxy to the index subject. Relative to the index subjects, proxy respondents tended to underreport the presence or level of exposure. For most exposures, odds ratios computed with proxy-derived data were similar in magnitude to odds ratios obtained with index subject data; important bias due to differential nonresponse or differential misclassification was suggested only for questions regarding hormone replacement therapy. Epidemiologic studies that rely on proxy respondents may require more subjects to offset the effect of nondifferential nonresponse and misclassification on the precision of effect estimates.
为评估代理受访者提供的暴露数据质量，我们在一项蛛网膜下腔出血的病例对照研究中采用了双重访谈方案。所有对照受试者及其代理受访者均接受了访谈（共283对对照-代理），能够自行提供信息的病例及其代理受访者也接受了访谈（共68对病例-代理）。代理提供的数据在人口统计学和身体体型测量方面的可靠性极佳（kappa值或组内相关系数范围为0.86 - 0.99），以及吸烟史的各个方面（范围为0.79 - 0.93）。对于有关药物和激素制剂的问题（范围为0.55 - 0.88）、饮酒情况（范围为0.52 - 0.82）以及休闲体育活动（范围为0.55 - 0.67），代理的可靠性略低。代理的可靠性因代理与指标受试者的关系而异。相对于指标受试者，代理受访者往往少报暴露的存在或水平。对于大多数暴露情况，用代理提供的数据计算的比值比在大小上与用指标受试者数据获得的比值比相似；仅在关于激素替代疗法的问题上提示存在因差异无应答或差异错误分类导致的重要偏差。依赖代理受访者的流行病学研究可能需要更多的受试者来抵消无差异无应答和错误分类对效应估计精度的影响。
