Assessment of inter-observer differences in the Italian multicenter study on reversible cerebral ischemia

A standardized protocol was used for duplicate examination by two neurologists of the clinical history and neurological signs in 55 patients with reversible cerebral ischemia. One trained examiner from each of eight clinical centres involved in the Italian Cooperative Study on reversible cerebral ischemia participated in this research. Duplicate examination were compared in order to evaluate the percentage of agreement achieved in the responses. Several discrepancies relating to either historical data or neurological signs were detected. Possible causes of this disagreement are discussed. The inter-observer differences appear to be an important problem to be faced in cooperative studies on reversible ischemic attacks. The purpose of the study was to estimate these differences in the attempt to increase the degree of agreement by repeated training sessions and discussion between the different examiners. These efforts are needed to improve the quality of clinical investigations on reversible cerebral ischemia and to increase the validity of their results.