Supplementary Material for: Population-Based Validation of the iScore for Predicting Mortality and Early Functional Outcome in Ischemic Stroke Patients

<b><i>Background:</i></b> We aimed to determine the accuracy of the iScore for predicting mortality and early disability following ischemic stroke in a French population-based study. <b><i>Methods:</i></b> 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. <b><i>Results:</i></b> 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). <b><i>Conclusion:</i></b> This is the first population-based study to demonstrate the accuracy of the iScore for predicting mortality and early disability in ischemic stroke patients.

<b><i>背景：</i></b> 本研究基于法国人群队列，旨在评估iScore预测缺血性脑卒中后死亡与早期残疾的准确性。<b><i>方法：</i></b> 本研究依托法国第戎市的人群脑卒中登记库，识别2006年至2011年间居住于该市的所有急性缺血性脑卒中患者，计算每位患者的30天iScore与1年iScore。采用logistic回归模型评估iScore预测30天及1年死亡率、出院时不良功能结局（改良Rankin量表评分3~6分）的效能。分别采用c统计量（c-statistic）与Hosmer-Lemeshow拟合优度检验（Hosmer-Lemeshow goodness-of-fit test）评估模型的区分度与校准度。<b><i>结果：</i></b> 本研究共登记1199例缺血性脑卒中患者，其中107例（8.9%）因至少一项数据缺失被排除。剩余1092例患者中，预测30天死亡率的c统计量为0.85（95%置信区间：0.82~0.89），预测1年死亡率的c统计量为0.84（95%置信区间：0.81~0.87）；Hosmer-Lemeshow拟合优度检验显示校准度良好（分别对应p=0.82与p=0.96）。针对残疾结局的分析得到相似结果：c统计量为0.81（95%置信区间：0.79~0.84），Hosmer-Lemeshow拟合优度检验p=0.45。<b><i>结论：</i></b> 本研究为首个基于人群队列的研究，证实iScore可准确预测缺血性脑卒中患者的死亡与早期残疾风险。