A method for examining common factor variance in multiple-component measuring instruments is outlined. The procedure is based on an application of the latent variable modeling methodology and is concerned with evaluating observed variance explained by a global factor and by one or more additional component-specific factors. The approach furnishes point and interval estimates of the proportion test score variance accounted for by the common factor and by the remaining factors, as well as of the difference in these proportions. The method is readily used in empirical behavioral research for purposes of addressing the issue of whether a scale under consideration is predominantly measuring a construct common to all its components, via application of the widely available software Mplus and R. The described procedure is illustrated using a numerical example. (Contains 2 tables, 1 figure, and 4 notes.)