Falkenström Fredrik, Hatcher Robert L, Holmqvist Rolf
Linköping University, Linkoping, Sweden Uppsala University, Uppsala, Sweden
City University of New York, New York, NY, USA.
Assessment. 2015 Oct;22(5):581-93. doi: 10.1177/1073191114552472. Epub 2014 Sep 29.
The working alliance concerns the quality of collaboration between patient and therapist in psychotherapy. One of the most widely used scales for measuring the working alliance is the Working Alliance Inventory (WAI). For the patient-rated version, the short form developed by Hatcher and Gillaspy (WAI-SR) has shown the best psychometric properties. In two confirmatory factor analyses of the WAI-SR, approximate fit indices were within commonly accepted norms, but the likelihood ratio chi-square test showed significant ill-fit. The present study used Bayesian structural equations modeling with zero mean and small variance priors to test the factor structure of the WAI-SR in three different samples (one American and two Swedish; N = 235, 634, and 234). Results indicated that maximum likelihood confirmatory factor analysis showed poor model fit because of the assumption of exactly zero residual correlations. When residual correlations were estimated using small variance priors, model fit was excellent. A two-factor model had the best psychometric properties. Strong measurement invariance was shown between the two Swedish samples and weak factorial invariance between the Swedish and American samples. The most important limitation concerns the limited knowledge on when the assumption of residual correlations being small enough to be considered trivial is violated.
工作联盟涉及心理治疗中患者与治疗师之间的合作质量。用于测量工作联盟的最广泛使用的量表之一是工作联盟量表（WAI）。对于患者自评版本，由哈彻和吉拉斯皮开发的简版（WAI-SR）显示出最佳的心理测量特性。在对WAI-SR的两次验证性因素分析中，近似拟合指数在普遍接受的规范范围内，但似然比卡方检验显示拟合不佳。本研究使用具有零均值和小方差先验的贝叶斯结构方程模型，在三个不同样本（一个美国样本和两个瑞典样本；N = 235、634和234）中检验WAI-SR的因素结构。结果表明，由于假设残差相关性恰好为零，最大似然验证性因素分析显示模型拟合不佳。当使用小方差先验估计残差相关性时，模型拟合非常好。两因素模型具有最佳的心理测量特性。两个瑞典样本之间显示出强测量不变性，瑞典样本和美国样本之间显示出弱因素不变性。最重要的局限性在于，对于何时违反残差相关性小到可以视为微不足道的假设，了解有限。
