Development and structural validation of a shortened version of the Participation Scale.

PURPOSE To validate a shortened version of the Participation Scale (P-scale) that will be quicker to use and to describe the factor structure found in the P-scale data in various study samples. METHODS A large multi-country and multi-cultural database was compiled consisting of 5125 respondents. Item analysis, explanatory factor analysis and confirmatory factor analysis were applied to identify items for deletion and investigate the factor structure of the P-scale. RESULTS The multi-country database included 11 databases from six different countries. Respondents were affected by a range of health conditions, including leprosy, HIV/AIDS, dermatological conditions and various disabilities. Of the respondents included 57% were male. The P-scale Short (PSS) contains 13 items. A two-factor structure, with factors named "work-related participation" (three items) and "general participation" (10 items), showed the best model fit (Comparative Fit Index = 0.983, Tucker Lewis Index = 0.979, Rooted Mean Square Error of Approximation = 0.061). The Cronbach's alphas were very good for both the whole scale and the subscales, 0.91, 0.83 and 0.90, respectively. Correlation between the two factors was high (r = 0.75) indicating that interpreting the P-scale as measuring an overall factor "participation" is still valid. A very high correlation (r = 0.99) was found between the full P-scale and the PSS. CONCLUSIONS The findings suggest good validity of the P-scale across a range of languages and cultures. However, field testing needs to confirm the validity of the PSS to measure the level of social participation restrictions across cultures and health conditions.