Psychometric properties of the Beck Depression Inventory and the Zung Self Rating Depression Scale in adults with mental retardation.

The psychometric properties of the Beck Depression Inventory and the Zung Self Rating Depression Scale were examined. Both tests were administered to 120 adults with mental retardation. Results were analyzed, correlated, and examined with principle component analysis. Findings suggest that the tests have good clinical utility with these persons and that depression may be more severe in people with mental retardation. Characteristics that can be employed in building other behavioral measures of depression for persons with mental retardation were also identified. Results show that there may be a tendency for persons with mental retardation to minimize distress report, further complicating the depression diagnostic process for these persons.