Disability and occupational assessment: objective diagnosis and quantitative impairment rating.

Industrial insurance originated in Europe in the nineteenth century and replaced the old system of negligence liability in the United States between 1910 and 1940. Today psychiatric disability assessments are performed by psychiatrists in the context of Social Security Disability Insurance applications, workers' compensation claims, private disability insurance claims, and fitness for duty evaluations. Expertise in the performance of psychiatric disability evaluations is required, but general psychiatric residency programs provide experience only with treatment evaluations, which differ fundamentally from independent medical evaluations as to role boundaries and the focus of assessment. Psychiatrists offer opinions regarding psychiatric impairments, but administrative or judicial tribunals make the actual determinations of disability. Social Security Disability Insurance evaluations and workers' compensation evaluations are discussed, as is the distinction between diagnoses, which are categorical, and impairment ratings, which are dimensional. Inconsistency in impairment ratings has been problematic in the United States and elsewhere in the workers' compensation arena. A protocol for achieving more consistent impairment ratings is proposed, one that correlates three commonly used global rating scales in a 3 × 5 grid, supplemented by objective psychological test data.