We examined whether a 9-item scale based on the theory of planned behavior (TPB)
predicted substance abuse treatment completion. Data were collected at a public, outpatient
program among clients initiating treatment (N= 200). Baseline surveys included measures of
treatment-related attitudes, norms, perceived control, and intention; discharge status was
collected from program records. As expected, TPB attitude and control components
independently predicted intention (model R-squared=. 56), and intention was positively …