Development and Pilot Testing of a Pharmacist-Led β-Lactam Allergy Risk Assessment Tool for Chinese Patients

Background: β-lactam allergy labels (BALs) are commonly found in patient records but are often inaccurate. This can lead to suboptimal antibiotic selection, increased healthcare costs, and antimicrobial resistance. Most existing risk assessment tools were developed in Western settings and are not applicable in Chinese clinical contexts. This study developed and pilot-tested a pharmacist-led BAL risk assessment tool tailored to the Chinese healthcare environment. Methods: The study was conducted in three phases: (1) A systematic review of 90 studies to identify key β-lactam allergy risk factors; (2) Grounded theory and text co-occurrence analysis to extract high-risk features and construct the assessment framework; and (3) A pilot implementation in a tertiary hospital to evaluate the tool’s feasibility, clinical impact, and patient outcomes using a quasi-experimental design. Results: The final tool comprised eight dimensions, 35 subdimensions, and over 1328 distinct coded nodes. Of the 289 patients involved in the pilot, 18.7% were classified as high risk. Compared with patients with BALs but without high-risk features, those at lower risk had significantly shorter hospital stays (8.5 ± 4.3 vs. 10.6 ± 5.5 days; p < 0.001), reduced hospitalization costs (17,800 ± 6200 vs. 21,000 ± 7500; p = 0.0011), and lower allergy event rates (0% vs. 6.5%; p = 0.002). β-lactam use increased (75.3% vs. 40.3%; p < 0.001), whereas second-line antibiotic use decreased (24.7% vs. 59.7%; p < 0.001). The tool also demonstrated high feasibility, achieving a 100% completion rate and strong adherence among pharmacists. Conclusion: This pharmacist-led risk assessment tool has strong potential for accurately identifying high-risk β-lactam allergy patients and optimising antimicrobial stewardship in Chinese hospitals. Further large-scale validation is warranted.