Galen Research, Manchester, UK.
J Invest Dermatol. 2012 Jan;132(1):76-84. doi: 10.1038/jid.2011.238. Epub 2011 Sep 1.
The Dermatology Life Quality Index (DLQI) is a widely used health-related quality of life measure. However, little research has been conducted on its dimensionality. The objectives of the current study were to apply Rasch analysis to DLQI data to determine whether the scale is unidimensional, to assess its measurement properties, test the response format, and determine whether the measure exhibits differential item functioning (DIF) by disease (atopic dermatitis versus psoriasis), gender, or age group. The results show that there were several problems with the scale, including misfitting items, DIF by disease, age, and gender, disordered response thresholds, and inadequate measurement of patients with mild illness. As the DLQI did not benefit from the application of Rasch analysis in its development, it is argued that a new measure of disability related to dermatological disease is required. Such a measure should use a coherent measurement model and ensure that items are relevant to all potential respondents. The current use of the DLQI as a guide to treatment selection is of concern, given its inadequate measurement properties.
皮肤病生活质量指数（DLQI）是一种广泛使用的健康相关生活质量衡量标准。然而，针对其维度的研究却很少。本研究的目的是应用 Rasch 分析对 DLQI 数据进行分析，以确定该量表是否具有单一维度，评估其测量特性，检验反应格式，并确定该测量方法是否存在疾病（特应性皮炎与银屑病）、性别或年龄组的差异项目功能（DIF）。结果表明，该量表存在几个问题，包括拟合不良的项目、疾病、年龄和性别 DIF、反应阈值紊乱以及对轻度疾病患者的测量不足。由于 Rasch 分析的应用并没有使 DLQI 受益，因此需要开发一种新的与皮肤病相关的残疾衡量标准。这样的衡量标准应该使用一致的测量模型，并确保项目与所有潜在的应答者相关。鉴于其测量特性不足，目前将 DLQI 作为治疗选择的指南是值得关注的。
