ASSESSMENT OF CLINICAL OUTCOMES IN ACUTE STROKE TRIALS

Background and Purpose-Adequate outcome assessment is crucial to rando mized trials. We wished to assess the types of outcomes used in acute stroke trials and the appropriateness of these outcomes and their anal yses. Methods-Acute stroke trials from the Cochrane Stroke Group's dat abase were included from 1955 to 1995 if they were published in full t ext in English. For each trial we collected year of publication, numbe r of patients randomized, blinding of outcome assessment, the specific outcome instruments used, the statistical methods used for analysis, and the significance of the results. The validity and reliability of e ach outcome measure were assessed by review of the Literature. Results -Our study included 174 trials. Outcomes were assessed blindly in 69%. Death was recorded in only 76% of trials, impairment in 76%, disabili ty in 42%, and handicap or quality of life in only 2%. Of the trials t hat measured impairment, 35% used a measure of established validity or reliability. For disability and handicap, the proportions with valid or reliable measures were 70% and 25%, respectively. Impairment and ha ndicap measures were primarily analyzed as continuous variables, while disability was mainly analyzed as a dichotomous variable. Continuous data were usually analyzed with inappropriate parametric statistics. T here was no relationship between the method of analysis, the type of o utcome, and the statistical significance of results. Conclusions-Most acute stroke trials up to 1995 have used clinical outcome measures tha t were inadequate in terms of their content, reliability, validity, bl inded assessment, and statistical analysis. This has important implica tions for future stroke research.