Population-based validation of the iScore for predicting mortality and early functional outcome in ischemic stroke...

We aimed to determine the accuracy of the iScore for predicting mortality and early disability following ischemic stroke in a French population-based study.

All patients with acute ischemic stroke were identified among residents of the city of Dijon, France, between 2006 and 2011, using a population-based stroke registry. The 30-day iScore and 1-year iScore were calculated. A logistic regression model was used to assess the performance of the iScore for predicting both 30-day and 1-year mortality, and poor functional outcome at discharge (modified Rankin Scale score of 3-6). The discrimination and calibration of the model were assessed using the c-statistic and the Hosmer-Lemeshow goodness-of-fit test, respectively.

Among the 1,199 ischemic stroke patients recorded, 107 (8.9%) were excluded because at least one item of data was missing. For the remaining 1,092 patients, the c-statistic was 0.85 (95% CI: 0.82-0.89) for 30-day and 0.84 (0.81-0.87) for 1-year mortality, and calibration was good (p = 0.82 and p = 0.96, respectively, for the Hosmer-Lemeshow test). Similar results were found for disability (c-statistic 0.81, 95% CI: 0.79-0.84, and p = 0.45 for the Hosmer-Lemeshow test).

This is the first population-based study to demonstrate the accuracy of the iScore for predicting mortality and early disability in ischemic stroke patients.