THE GENERALIZABILITY OF BRIEF RATINGS OF PSYCHOSOCIAL FUNCTIONING

The multivariate generalizability of the Role Functioning Scale (RFS), serving as a replacement for the Social Adjustment Scale global ratin gs, was investigated. Severely mentally disturbed clients of a public mental health bureau, who were participating in one of two clinical tr ials that compared the cost-effectiveness of case management or substa nce abuse services, were interviewed and rated by psychiatric technici ans, operating as four-person teams. The generalizability of single su bscales was notably less than the generalizability of the combination of four subscales. Still larger differences in generalizability were n oted between proposed future applications of the RFS that might employ one, as opposed to more than one, interviewer. Variations in the powe r to detect differences in service effectiveness were related to the l evels of generalizability. Applications of this, or any brief rating i nstrument should benefit from estimating the generalizability of the r atings for the proposed studies and employing estimates of generalizab ility to adjust sample size requirements.