Validation of a screening instrument for studying the prevalence of cerebrovascular diseases in the Chilean population

: We assessed a screening instrument, adapted from a model suggested by WHO, aimed to perform population studies on the prevalence of cerebrovascular disease in Chile. Sixty-two subjects, 31 with cerebrovascular diseases and 31 without, were asked about symptoms and requested to do simple movements by trained interviewers. The results of the instrument were compared with a neurological examination performed by two specialists. Global sensitivity and specificity of the instrument, using WHO evaluation criteria, were 100 and 38.7% respectively. When three or more symptoms and one positive sign were considered as cutoff points, global specificity increased to 61% and sensitivity decreased to 93%. It is concluded that the present instrument is highly sensitive but lacks specificity.