Common method variance and specification errors: A practical approach to detection

The purpose of this study was to demonstrate how examining the bivariate co rrelations between items in self-report measures can assist in differentiat ing between possible common method variance vs. model specification errors. Specifically, social desirability was viewed as either a possible source o f common method variance or as a theoretically meaningful construct that sh ould be included in the model of interest (i.e., a specification error). In the first instance, LISREL was used, and the level of correlation between measures of social desirability and measures of the five constructs of inte rest was manipulated. These results provided some insight as to when one ne eds to be concerned about the possible "common variance effects" on the str uctural model. In the second instance, the correlations between measures of social desirability and the measures of only two constructs of interest we re again manipulated. These analyses illustrated the point at which the omi ssion of social desirability as a theoretically relevant variable began to result in a poor fit of the structural model.