Drug-related emergency department visits in older patients: an applicability and reliability study of an existing assessment tool

Background AT-HARM10 is a research tool to identify possible drug-related hospital admissions. It is unclear whether the tool can be applied to emergency department visits as well. Aim The aim of this study was to investigate the applicability and reliability to identify drug-related emergency department visits in older patients with AT-HARM10. Method A random sample of 400 patients aged 65 years or older from a clinical trial in four Swedish hospitals was selected. All patients' emergency department visits within 12 months after discharge were assessed with AT-HARM10. The main outcome measures were the percentage of successfully assessed visits for applicability and the interrater reliability (Cohen's kappa). Results Of the initial sample (n = 400), 113 patients [median age (interquartile range): 81 (76-88) years] had at least one emergency department visit within 12 months. The patients had in total 184 visits, of which 179 (97%) were successfully assessed. Fifty-three visits (29%) were possibly drug-related. The Cohen's kappa value was 0.70 (substantial). Conclusion It seems applicable and reliable to identify possible drug-related emergency department visits in addition to hospital admissions in older patients with AT-HARM10. As a consequence, the tool has been updated to support its novel use in clinical research.