An Item Response Theory Analysis of The Questionnaire of God Representations

The Dutch Questionnaire of God Representations (QGR) was investigated bymeans of item response theory (IRT) modeling in a clinical (n = 329) and anonclinical sample (n = 792). Through a graded responsemodel and IRT-baseddifferential functioning techniques, detailed item-level analyses and informationabout measurement invariance between the clinical and nonclinicalsample were obtained. On the basis of the results of the IRT analyses, ashortened version of the QGR (S-QGR) was constructed, consisting of 22items, which functions in the same way in both the clinical and the nonclinicalsample. Results indicated that the QGR consists of strong and reliable scaleswhich are able to differentiate among persons. Psychometric characteristics ofthe S-QGR were adequate