Examining discriminant validity issues of the Sport Motivation Scale-6.

The current study was conducted to re-assess the factor structure of the 24-item Sport Motivation Scale-6 (SMS-6; Mallett, Kawabata, Newcombe, Otero-Forero, & Jackson, 2007) with an independent sample. A total of 437 participants completed the SMS-6, and their responses were examined with confirmatory factor analysis and recent exploratory structural equation modelling (Asparouhov & Muthén, 2009). A six-factor confirmatory-factor-analysis model did not fit to the sample data adequately. Through examination of the corresponding exploratory-structural-equation-modelling solution, it was found that two items loaded on non-target factors poorly. This result was replicated by a published data set (Mallett, Kawabata, Newcombe, et al., 2007). The modified confirmatory-factor-analysis model with these two items removed fit to the present study's data satisfactorily and all six factors were adequately diferentiated. These results generally validate the SMS-6 responses. Furthermore, this study demonstrated the usefulness of a comparison of confirmatory-factor-analysis and exploratory-structural-equation-modelling solutions for an accurate interpretation of individual parameters.