Evaluating the use of the ABCD2 score as a clinical decision aid in the emergency department: Retrospective observational study

Clinical decision aids (CDAs) can help clinicians with patient risk assessment. However, there is little data on CDA calculation, interpretation and documentation in real-world ED settings. The ABCD2 score (range 0-7) is a CDA used for patients with transient ischaemic attack (TIA) and assesses risk of stroke, with a score of 0-3 being low risk. The aim of this study was to describe ABCD2 score documentation in patients with an ED diagnosis of TIA. Retrospective observational study of patients with a working diagnosis of a TIA in two Australian EDs. Data were gathered using routinely collected data from health informatics sources and medical records reviewed by a trained data abstractor. ABCD2 scores were calculated and compared with what was documented by the treating clinician. Data were presented using descriptive analysis and scatter plots. Among the 367 patients with an ED diagnosis of TIA, clinicians documented an ABCD2 score in 45% (95% CI 40-50%, n = 165). Overall, there was very good agreement between calculated and documented scores (Cohen's kappa 0.90). The mean documented and calculated ABCD2 score were similar (3.8, SD = 1.5, n = 165 vs 3.7, SD = 1.8, n = 367). Documented scores on the threshold of low and high risk were more likely to be discordant with calculated scores. The ABCD2 score was documented in less than half of eligible patients. When documented, clinicians were generally accurate with their calculation and application of the ABCD2. No independent predictors of ABCD2 documentation were identified.