Taylor Jeremy M G, Cooper Kristine L, Wei John T, Sarma Aruna V, Raghunathan Trivellore E, Heeringa Steve G
Department of Biostatistics, University of Michigan, Ann Arbor 48109, USA.
Am J Epidemiol. 2002 Oct 15;156(8):774-82. doi: 10.1093/aje/kwf110.
The Flint Men's Health Study is an ongoing population-based study of African-American men designed to address questions related to prostate cancer and urologic symptoms. The initial phase of the study was conducted in 1996-1997 in two stages: an interviewer-administered survey followed by a clinical examination. The response rate in the clinical examination phase was 52%. Thus, some data were missing for clinical examination variables, diminishing the generalizability of the results to the general population. This paper is a case study demonstrating the application of multiple imputation to address important questions related to prostate cancer and urologic symptoms in a data set with missing values. On the basis of the observed clinical examination data, the American Urological Association Symptoms Score showed a surprising reduction in symptoms in the oldest age group, but after multiple imputation there was a monotonically increasing trend with age. It appeared that multiple imputation corrected for nonresponse bias associated with the observed data. For other outcome measures-namely, the age-adjusted 95th percentile of prostate-specific antigen level and the association between urologic symptoms and prostate volume-results from the observed data and the multiply imputed data were similar.
弗林特男性健康研究是一项正在进行的基于人群的针对非裔美国男性的研究，旨在解决与前列腺癌和泌尿系统症状相关的问题。该研究的初始阶段于1996年至1997年分两个阶段进行：先是由访员进行的问卷调查，随后是临床检查。临床检查阶段的应答率为52%。因此，临床检查变量存在一些缺失数据，这降低了研究结果对普通人群的普遍适用性。本文是一个案例研究，展示了多重填补法在一个存在缺失值的数据集中用于解决与前列腺癌和泌尿系统症状相关重要问题的应用。基于观察到的临床检查数据，美国泌尿外科学会症状评分显示最年长年龄组的症状有惊人的减少，但经过多重填补后，症状随年龄呈单调递增趋势。似乎多重填补法校正了与观察到的数据相关的无应答偏倚。对于其他结局指标，即前列腺特异性抗原水平的年龄调整第95百分位数以及泌尿系统症状与前列腺体积之间的关联，观察到的数据和多重填补后的数据结果相似。
