Rathouz P J, Kasper J D, Zeger S L, Ferrucci L, Bandeen-Roche K, Miglioretti D L, Fried L P
Department of Health Studies, School of Medicine, University of Chicago, IL, USA.
Am J Epidemiol. 1998 Apr 15;147(8):764-73. doi: 10.1093/oxfordjournals.aje.a009521.
The assessment of physical functioning and disability is integral to population-based and clinical research carried out among elderly people. Typically, functional status is measured through self-reported responses to questions of the form "Do you have difficulty [doing a specific task]?" Knowledge of the reliability and validity of these self-report measures is key to the interpretation of many research efforts, but data on these measurement parameters are sparse. This paper addresses this deficiency through analyses of data from the Weekly Substudy of the Women's Health and Aging Study, a cohort of Baltimore-area women aged > or =65 years with moderate to severe physical disability. Self-reported data on 20 activities, obtained weekly over a 6-month period in 1993 or 1994, were analyzed to investigate how time intervals between assessments and a subject's age and baseline level of disability influenced the consistency of self-reports of disability at both the population level and the individual level. The prevalence of self-reported difficulty increased with baseline disability and, to a lesser extent, with age group. Consistency for all items was very high over short time intervals, but it decreased substantially with increasing intervals between responses (although associations between responses remained significant at 24 weeks). Consistency did not vary with age or baseline disability. Graphic techniques and statistical methods for use with repeated binary data are also illustrated.
对身体功能和残疾状况的评估是针对老年人开展的基于人群和临床研究的重要组成部分。通常，功能状态是通过对“您在[做某项特定任务]方面有困难吗？”这类问题的自我报告回答来衡量的。了解这些自我报告测量方法的信度和效度是许多研究工作解读的关键，但关于这些测量参数的数据却很稀少。本文通过对妇女健康与衰老研究每周子研究的数据进行分析来解决这一不足，该研究队列是巴尔的摩地区年龄≥65岁且有中度至重度身体残疾的女性。分析了1993年或1994年在6个月期间每周获取的关于20项活动的自我报告数据，以研究评估之间的时间间隔以及受试者的年龄和残疾基线水平如何在人群层面和个体层面影响残疾自我报告的一致性。自我报告困难的患病率随基线残疾程度增加而上升，在较小程度上也随年龄组增加而上升。在短时间间隔内，所有项目的一致性都非常高，但随着回答之间间隔时间的增加，一致性大幅下降（尽管在24周时回答之间的关联仍然显著）。一致性并不随年龄或基线残疾程度而变化。本文还阐述了用于重复二元数据的图形技术和统计方法。
