Development and Validation of a Mobile Clinical Decision Support Tool for the Diagnosis of Drug Allergy in Adults: The Drug Allergy App

Abstract

Penicillin allergy overdiagnosis has been associated with inappropriate antibiotic prescribing, increased antimicrobial resistance, worse clinical outcomes, and increased health care costs. To develop and validate a questionnaire-based algorithm built in a mobile application to support clinicians in collecting accurate history of previous reactions and diagnosing drug allergy appropriately. A survey was completed by 164 medical and nonmedical prescribers to understand barriers to best practice. Based on the survey recommendations, we created a 10-item questionnaire-based algorithm to allow classification of drug allergy history in line with the National Institute for Health and Care Excellence guidelines on drug allergy. The algorithm was incorporated into a mobile application and retrospectively validated using anonymized clinical databases at regional immunology and dermatology centers in Manchester, United Kingdom. A total of 55.2% of prescribers (95% confidence interval, 47% to 63.4%) thought it impossible to draw a firm conclusion based on history alone and 59.4% (95% CI, 51.4% to 67.5%) believed that regardless of the details of the penicillin allergy history, they would avoid all β-lactams. A drug allergy mobile application was developed and retrospectively validated, which revealed a low risk for misclassification of outcomes compared with reference standard drug allergy investigations in the allergy and dermatology clinics. Perceived lack of time and preparedness to collect an accurate drug allergy history appear to be important barriers to appropriate antimicrobial prescribing. The Drug Allergy App may represent a useful clinical decision support tool to diagnose drug allergy correctly and support appropriate antibiotic prescribing.