PSYCHOMETRIC EVALUATION OF THE SITUATIONAL CONFIDENCE QUESTIONNAIRE IN ADOLESCENTS - FITTING A GRADED ITEM RESPONSE MODEL

Self-efficacy theory has been extensively applied to alcoholism treatm ent, theories of relapse, and relapse prevention. Most empirical studi es of perceived self-efficacy to resist heavy drinking have used the S ituational Confidence Questionnaire (SCQ). Among adults, this instrume nt has been shown to be psychometrically sound. Little is known, howev er, about the psychometric properties of the SCQ in the adolescent pop ulation. We administered the SCQ to a sample of 662 adolescents to eva luate its psychometric properties. Each of the eight subscales was fou nd to be unidimensional. Invariance of the item parameters across diff erent groups was also examined. The reliability coefficients, based on item response theory (marginal reliability) and classical measurement theory (Cronbach alpha), were found to be high. These results demonst rate that the SCQ is appropriate for use among adolescents.