项目反应理论在医学量表条目筛选中的应用

The application of item response theory in screening item of medical scale

本文着重介绍项目反应理论(IRT)的基本特征及其在医学量表编制和修订中的具体应用。IRT具有项目参数不变性,可以为条目和量表提供信息量及不同潜在能力对应的测量信度。因此,IRT主要从项目参数、项目特征曲线、个体-条目图、条目对模型的拟合情况、条目信息量、条目在不同群体上的项目功能差异等方面判断条目的优劣。

This article focuses on the basic features of item response theory （IRT） and the specific application in the establishment and revision of medical scale. The item parameters of IRT have the nature of invarianee, so IRT can pro vide the information of item and scale, and the measurement reliability of different potential ability. Therefore, IRT judges the merits of item from the item parameters, item characteristic curve, the individual-item chart, fit of the mod- el, the amount of information and DIF in different groups.