Objective. The purpose of this study was to examine the discriminant validity of the Assessment of Motor and Process Skills (AMPS) when used to evaluate a heterogeneous sample of subjects with psychiatric disorders.

Method. Sixty subjects, ranging in age from 16 to 72 years, participated in this study; 30 were persons without disorders living in the community; 30 had diagnosed psychiatric disorders. Two univariate F tests were used to test the hypothesis that mean AMPS measures would differ significantly between the group with and the group without psychiatric disorders.

Results. The hypothesis was supported for both AMPS motor and process scale measures. As would be expected among a sample that includes many higher functioning persons, many subjects with psychiatric disorders did just as well as subjects in the group without psychiatric disorders.

Conclusions. Motor as well as process skill abilities of persons with psychiatric disorders should be evaluated. Because the AMPS provides more specific features than other global functional instruments, it can help clinicians plan treatment and intervention more effectively. Further examination of the motor and process skill deficits within and among diagnostic subgroups and of the effect of medication and prolonged hospitalization on AMPS motor and process abilities is indicated.