Locus of control as predictor of compliance and outcome in treatment of encopresis.

We examined the effectiveness of instruments that describe a child's locus of control and perceived self-competence as predictors of outcome in the treatment of encopresis. Fifty children 9 to 12 years of age completed such instruments prior to clinical interview. Clinicians were blind as to the results of these questionnaires and administered a standard encopresis protocol to all patients. Six to 17 months later, 45 (90%) of the patient's parents were interviewed to assess compliance and treatment outcome. Children who significantly improved had a more internal locus of control (P less than 0.05) and better compliance (P less than 0.05) as determined by two separate outcome variables. Locus of control and compliance were not, however, significantly correlated with each other; each appeared to have an independent association with outcome. There was no association between perceived self-competence and outcome. The positive association between locus of control and outcome was not mediated by socioeconomic status, age, duration of encopresis, severity of encopresis, gender, or time between initiation of treatment and follow-up. Measurement of locus of control in children with encopresis appears to be helpful in identifing a group at high risk for resistance of treatment.