The Group Questionnaire: A psychometric investigation of the Dutch adaptation among patients with personality disorders.

<b><i>Objective</i></b>: The Group Questionnaire (GQ; Krogel et al., 2013) intends to measure important group processes such as group climate, group cohesion, and the quality of group relationships. The aim of the present study was to investigate the psychometric properties of the Dutch version of the GQ (GQ-NL) in a clinical population with personality disorders. <br/><b><i>Method</i></b>: The English version of the questionnaire was translated into Dutch using a standard “forward–backward” translation procedure. The study included 439 outpatients who received group therapy. Internal consistency reliability was assessed by Cronbach’s α. Construct validity was investigated by evaluating the factor structure of the original questionnaire with confirmatory factor analysis. For examining convergent validity, a subsample of 243 patients completed four other questionnaires measuring similar group concepts. <br/><b style=""><i>Results</i></b>: The factor structure of the original questionnaire was largely replicated for the Dutch version, with adequate fit of the model with eight subfacets and of the full second-order model. Fit improved when correlation between three item pairs and three latent leader aspects was allowed. The internal consistency of the scales and facets was good; convergent validity was supported. <br/><b style=""><i>Conclusion</i></b>: Previous reports on the good psychometric properties of the GQ are substantiated with the present results for the Dutch version. The factor structure of the GQ-NL with three latent factors and eight subfacets was supported, as was the validity and reliability of the instrument for use in research and clinical practice. Further research with a larger sample size and different patient groups is recommended.