Development, reliability, and validity of the Measure of Sexual Identity Exploration and Commitment (MOSIEC)

Four studies were conducted on the development and validation of the Measure of Sexual Identity Exploration and Commitment (MoSIEC). Exploratory factor analysis of an initial item pool yielded a 22-item measure with 4 distinct factors assessing commitment, exploration, sexual orientation identity uncertainty, and synthesis/integration. Exploratory factor analysis findings support the argument that sexual identity is a broad, multidimensional construct and that the MoSIEC assesses the construct of sexual identity in a manner consistent with J. E. Marcia's (1966) model of identity development. Confirmatory factor analyses demonstrated the stability of the MoSIEC factor structure, providing evidence of construct validity. Test-retest stability, internal consistency, and validity coefficients supported the use and continued development of the MoSIEC. Significant differences in levels of exploration and sexual orientation identity uncertainty were found among different sexual orientation identity groups, establishing the criterion-related validity of the MoSIEC. Implications for further development and use of the MoSIEC are discussed.