Confirmatory factor analysis of the Penn State Worry Questionnaire.

Worry is often assessed with the 16-item Penn State Worry Questionnaire (PSWQ; Meyer, Miller, Metzger, & Borkovec, 1990. Behaviour Research and Therapy, 28, 487-495), but the factor structure of the PSWQ is not well articulated. Three factor analyses of the PSWQ have been conducted, with two (Brown, Antony, & Barlow, 1992. Behaviour Research and Therapy, 30, 33-37; van Rijsoort, Emmelkamp, & Vervaeke, 1999) retaining a unifactorial solution and one (Stöber, 1995) retaining a two-factor solution. We sought to determine the relative strengths of these solutions. Seven hundred eighty-eight undergraduates completed the PSWQ and measures of depression and anxiety. Confirmatory factor analyses indicated that the two-factor solution provided a better fit to the data. There was also evidence for a higher order worry factor. Multiple regression analyses revealed that factor 1 (Worry Engagement) explained the majority of the variance in the symptom measures. The higher order worry factor also accounted for variance in some measures. Compared to the PSWQ total score, Worry Engagement demonstrated slightly higher internal consistency and significantly stronger correlations with most measures of depression and anxiety. Factor 2 (Absence of Worry) demonstrated moderate negative correlations with Worry Engagement and the PSWQ Total Score but only modest correlations with depression and anxiety.