A study of 128 consecutive patients with thromboembolic stroke in a rehabilitation hospital from July 1988 to September 1990 found a prevalence of major depression of 17%. The patient population was described according to the principles of the World Health Organization's (WHO) International Classification of Impairments, Disabilities and Handicaps (ICIDH) according to biological impairment, measured by computerized tomography (CT) scanning of the brain and side of hemiparesis and physical disability, measured by functional movement and activities of daily living. Handicap, referring to the interaction between disability and the environmental situation, often defined as the subjective disadvantage of being ill, was not measured in this study. A stroke index with four items was generated from the parameters describing biological impairment and physical disability. The psychiatric rating scales (the 17-item Hamilton Scale for Depression (HAM-D), the Melancholia Scale [MES]and the Newcastle Diagnostic Depression Scale), and the new stroke-index showed adequate coefficients of Cronbach's alpha and Loevinger, suggesting that these scales have both adequate item correlation and homogeneity (adequate hierarchical structure). The impairment disability index of stroke thus seems to be a meaningful measurement of the specific factors of this disease. There was no correlation between the stroke-index and the psychiatric rating scales measuring the emotional dimension of disability caused by the disease expressed as depression. The results suggest that the depression found among stroke patients is not a simple reaction to the physical disability of the stroke.