Veddegjærde Kari-Elise Frøystad, Sivertsen Børge, Wilhelmsen Ingvard, Skogen Jens Christoffer
Department of Clinical Science, University of Bergen, Bergen, Norway; Division of Mental Health, Norwegian Institute of Public Health, Bergen, Norway; Department of Medicine, Haraldsplass Deaconess Hospital, Bergen, Norway.
Division of Mental Health, Norwegian Institute of Public Health, Bergen, Norway; Uni Health, Uni Research, Bergen, Norway; Department of Psychiatry, Helse Fonna HF, Haugesund, Norway.
J Psychosom Res. 2014 Sep;77(3):213-8. doi: 10.1016/j.jpsychores.2014.06.011. Epub 2014 Jun 28.
The Whiteley Index (WI) is a widely used screening instrument for health anxiety/hypochondriasis. Several studies have previously explored the psychometric properties of the WI, but with mixed findings concerning both item composition and factor structure. The main aim of the current study was to examine different factor structures as identified from previous studies using data from a large general population based study. We also wanted to provide gender specific norms.
Data were taken from a large population-based study in Norway, the Hordaland Health Study (HUSK N=7274). Confirmatory factor analysis (CFA) of several models of the WI was conducted. Item response theory (IRT) analysis was performed on the model with the best goodness-of-fit.
CFA of all previously proposed factor models of the WI revealed clearly inadequate model fits. The IRT analysis suggested that a six-item model best described the data, and CFA confirmed an adequate goodness-of-fit across indices.
The current study found evidence for a six-item, single-factor model of the WI. Our findings suggest that this abbreviated version has the best factor structure compared to previously proposed factor models. We recommend that the factor structure identified in this study should be investigated further in independent samples.
怀特利指数（WI）是一种广泛用于筛查健康焦虑/疑病症的工具。此前已有多项研究探讨了WI的心理测量特性，但在项目构成和因子结构方面的结果不一。本研究的主要目的是利用一项基于大样本人群的研究数据，检验先前研究中确定的不同因子结构。我们还希望提供特定性别的常模。
数据取自挪威一项基于大样本人群的研究——霍达兰健康研究（HUSK，N = 7274）。对WI的几种模型进行了验证性因子分析（CFA）。对拟合优度最佳的模型进行了项目反应理论（IRT）分析。
对WI所有先前提出的因子模型进行的CFA显示模型拟合明显不足。IRT分析表明，一个六项模型能最好地描述数据，CFA也证实该模型在各项指标上拟合良好。
本研究发现了WI的一个六项单因子模型的证据。我们的研究结果表明，与先前提出的因子模型相比，这个简化版本具有最佳的因子结构。我们建议在独立样本中进一步研究本研究中确定的因子结构。
