A 16-item Children's Motivation Scale (CMS) was developed to evaluate
level of motivation in children and adolescents. The study population
consisted of a normative sample of 290 school children and a clinical
sample of 165 child and adolescent psychiatric patients, Test-retest,
internal consistency, and interrater reliability were fair to good for
both samples, Validity of the CMS was demonstrated by its ability to
differentiate clinical from normative samples according to the level o
f motivation, by a significant correlation of the CMS with an independ
ent measure of withdrawal, and by its lack of correlation with an inde
pendent measure of depression. Principal components analysis identifie
d a three-component structure. These findings support the conclusion t
hat the CMS accesses a clinically important but often overlooked psych
iatric construct.