Kempen G I, Myers A M, Powell L E
Northern Centre for Health Care Research, School of Medicine, University of Groningen, The Netherlands.
J Clin Epidemiol. 1995 Nov;48(11):1299-305. doi: 10.1016/0895-4356(95)00043-7.
The results of a Canadian study have shown that a set of 12 (I)ADL items did not meet the criteria of Guttman's scalogram program, questioning the assumption of hierarchical ordering. In this article, the hierarchical structure of (I)ADL items from the Canadian elderly sample is retested with another scalogram program, and both the epidemiological research and clinical applications of hierarchical scales are discussed. For retesting the hierarchical structure, Mokken's Stochastic Scale Program was used. When item distributions were not too skewed, the existence of one general dimension with two (correlated) subdimensions were clearly found. The analyses for scalability showed that, except in the case of extremely skewed item distributions, the data set met the criteria of Mokken's Stochastic Scale Program, indicating a hierarchical structure of the items. The scalability of a set of items is affected by the sample studied, the choice of response options for each item, the selection and number of items in the scale, and the type of scaling procedure. The practical assumptions of hierarchy should be restricted to program planning and epidemiological research purposes only. For clinical assessment, a finer grading is desirable and all questions on an ADL/IADL inventory should be asked for each individual.
一项加拿大研究的结果表明，一组12项日常生活活动（IADL）项目不符合古特曼量表程序的标准，这对层次排序的假设提出了质疑。在本文中，使用另一种量表程序对来自加拿大老年样本的IADL项目的层次结构进行重新测试，并讨论了层次量表的流行病学研究和临床应用。为了重新测试层次结构，使用了莫肯随机量表程序。当项目分布不太偏态时，明显发现存在一个具有两个（相关）子维度的一般维度。可扩展性分析表明，除了项目分布极其偏态的情况外，数据集符合莫肯随机量表程序的标准，表明项目具有层次结构。一组项目的可扩展性受所研究的样本、每个项目的回答选项选择、量表中项目的选择和数量以及量表程序的类型影响。层次结构的实际假设应仅限制在项目规划和流行病学研究目的。对于临床评估，需要更精细的分级，并且应该针对每个个体询问ADL/IADL清单上的所有问题。
