Prognostic value of the ABCD2 clinical prediction rule: a systematic review and meta-analysis

Purpose: The ABCD2 clinical prediction rule (CPR) is designed to predict early risk of stroke after transient ischaemic attack (TIA). The purpose of this systematic review with meta-analysis is to determine the predictive value of the ABCD2 at 7 and 90 days across three strata of risk. Methods: A systematic literature search was conducted to identify studies that validated the ABCD2. The derived rule was used as a predictive model and applied to subsequent validation studies. Comparisons were made between observed and predicted number of strokes stratified by risk group, low (0-3 points), moderate (4-5 points) and high (6-7 points). Pooled results are presented as risk ratios (RRs) with 95% confidence intervals, in terms of over-prediction (RR>1) or under-prediction (RR0.05). Conclusion: The ABCD2 is a useful CPR, particularly in relation to 7 day risk of stroke.