A test of the reliability and validity of the Multnomah Community Ability Scale.

Previous research shows that the Multnomah Community Ability Scale (MCAS) total score is reliable and has predictive validity. This study evaluates the MCAS total and sub-scale scores on a sample of 1,250 outpatient mental health clients in Washington State. The MCAS sub-scales are reliable, and there is evidence for their concurrent validity. However, the factor structure of the MCAS only partially replicated the hypothesized sub-scales, and the authors recommend that sub-scales as currently constructed not be used as performance indicators. If only the total MCAS is of interest to users, the authors recommend using the single-item SOFAS rather than the 17-item MCAS.