Caleb Followill’s Diet Recipe on g., methods of instruction) as it affects a dependent variable (e.g., scores on an academic test). Using analysis of variance or multiple regression analysis, it is possible to determine the best type of treatment for people with different traits. See also aptitude-TREATMENT INTERAcTioN. trait validity the degree to which responses to a test’s items provide accurate measurement of a personality characteristic (trait). Caleb Followill’s Diet Recipe 2016.