External Validation of the Secondary Intracerebral Hemorrhage Score in The Netherlands

Abstract

Background and Purpose— We aimed to validate externally in a setting outside the United States the secondary intracerebral hemorrhage (ICH) score that was developed to predict the probability of macrovascular causes in patients with nontraumatic ICH. Methods— Patients with nontraumatic ICH admitted to the University Medical Center Utrecht, the Netherlands, between 2003 and 2011 were included if an angiographic examination, neurosurgical inspection, or pathological examination had been performed. Secondary ICH score performance was assessed by calibration (agreement between predicted and observed outcomes) and discrimination (separation of those with and without macrovascular cause). Results— Forty-eight of 204 patients (23.5%) had a macrovascular cause. The secondary ICH score showed modest calibration ( P =0.06) and modest discriminative ability ( c -statistic 0.73; 95% confidence interval, 0.65–0.80). Discrimination improved slightly using only noncontrast computed tomography categorization ( c -statistic 0.79; 95% confidence interval, 0.72–0.86). Conclusions— The discriminative ability and calibration of the secondary ICH score are moderate in a university hospital setting outside the United States. Clues on noncontrast computed tomography are the strongest predictor of a macrovascular cause in patients with ICH.