Factorial validity, reliability, and measurement invariance of the Negative Physical Self Scale in a sample of men residing in North America

The Negative Physical Self Scale (NPSS) is a measure of body dissatisfaction that was developed for administration within an Asian sample and has recently been translated to English and validated for use in North American female samples. The aim of the present study was to examine the factor structure and measurement invariance of the English-translated version of the NPSS across three ethnic groups (i.e., Caucasian, Asian, and other) using a sample of men residing in North America. Additionally, the internal consistency, convergent validity, and incremental validity of the NPSS were examined. A sample of 534 young (aged between 18 and 25) North American men completed self-report measures of the NPSS, the Body Shape Questionnaire, the Eating Disorder Examination Questionnaire, and the Male Body Attitudes Scale. Confirmatory factor analysis was conducted on two hypothesized models. The results supported the second-order factor structure (four factors with three subdimensions). Overall, we found that the factor structure and factor loadings of the NPSS were equal in participants across three broad ethnic categories (i.e., Caucasian, Asian, and other). Likewise, the NPSS displayed first-order scalar invariance. Further, the NPSS test scores demonstrated high internal consistency, strong convergent validity, and incremental validity over and above the existing measures of body dissatisfaction, body attitudes, and disordered eating. In sum, the English version of the NPSS is a valid and appropriate measure to assess body dissatisfaction in men residing in North America.