A comparison of five stroke scales with measures of disability, handicap, and quality of life.

Abstract
Recently much debate has arisen on the appropriateness of assessing stroke outcomes with stroke impairment scales. Our purpose was to study the relationship between long-term impairments and functional outcomes in terms of disability, handicap, and quality of life. We studied 87 patients who had a stroke 6 months earlier. Impairments were scored on five stroke scales: the Orgogozo Scale, the National Institutes of Health scale, the Canadian Neurological Scale, the Mathew scale, and the Scandinavian Stroke Scale. Disability was assessed with the Barthel Index, handicap with the Rankin scale, and quality of life with the Sickness Impact Profile. The linear relationship between stroke scales and functional scales was assessed with correlation coefficients. We used regression analyses to explain functional health. The stroke scales were highly related to one another (range, r = -.85 to .92). The correlation between stroke scales and functional scales was < .70 and decreased from Barthel (mean r2 = 47.5%) to Rankin (mean r2 = 36.5%) to Sickness Impact Profile (mean r2 = 33%). Stroke scales were rather poorly correlated with patients' psychosocial conditions (mean r2 = 11.5%). Functional health status was mainly related to leg power and orientation. The standardized stroke scale weights of the explanatory items were lower than their standardized regression weights. Stroke scales only partly explain functional health. The impact of impairments on functional outcomes seems to be underestimated by the stroke scale weights. The correlation patterns give empirical support to the hierarchical structure of the International Classification of Impairments, Disabilities and Handicaps.