Discrepancies and Quality of Medication Allergy Documentation Between Primary Care and Hospital Information Systems: A Retrospective Cohort Study

Background and Objective: Accurate medication allergy documentation is essential for patient safety. This study evaluated discrepancies and documentation quality between medication allergy records in the primary care information system (AP-Madrid) and the Hospital Clinical Information System (HCIS) at a tertiary care hospital. Methods: A retrospective cohort study included 223 patients with medication allergy records during 2022. Agreement between systems was assessed using Cohen’s kappa, and documentation quality was classified as adequate, moderate, or poor based on four predefined parameters. Results: Agreement between AP-Madrid and HCIS was poor (Cohen’s κ = −0.25). Of the 223 patients, medication allergy records were documented exclusively in HCIS for 94 patients, exclusively in AP-Madrid for 36 patients, and in both systems for 88 patients, while 5 patients had medication allergy information identified only in free-text clinical documentation. Documentation quality was predominantly poor in both HCIS (60.4%, n = 134) and AP-Madrid (61.9%, n = 138). Beta-lactam antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs) were the most frequently implicated therapeutic groups. Two positive medication re-exposure events were identified. Conclusions: Substantial discrepancies and poor documentation quality were identified between primary care and hospital medication allergy records, highlighting limited interoperability between the two systems. Improving the completeness, consistency, and standardized exchange of medication allergy information across healthcare settings may enhance patient safety and continuity of care.