Abstract: Objective To analyze the rationality of outpatient prescriptions in a large tertiary hospital (this hospital) so as to provide reference for clinically proper use of drugs. Methods The rationality of prescriptions for outpatients in this hospital between June 2018 and May 2019 was evaluated by manual review. The primary, secondary and common causes of irrational prescriptions for outpatients were analyzed with the Pareto diagram. Results A total of 23 658 prescriptions were evaluated, including 1022 irrational prescriptions that accounted for 4.32%. The leading cause was indication mismatch and incomplete writing of clinical diagnosis. The secondary cause was improper usage or dosage. The common causes included sub-standard clinical diagnosis, inappropriate combinations of drugs, improper formulations or routes of administration, poor selection of drugs, repeated administration and contraindications. Conclusion The Pareto diagram can help identify problems with prescriptions and improve the level of rational clinical use of drugs in hospitals.

Key words: irrational clinical use, review of prescriptions for outpatients, Pareto chart analysis