Objective

To determine the nature, extent, and cost of discrepancies between the quantities of medications supplied to medical departments and administered to patients in public hospitals.

Design

Multicentre, retrospective observational study; analysis of electronic pharmacy drug management system (medication supply) and medication administration data for twenty frequently used medications.

Setting, participants

Medical, surgical, and emergency department (ED) wards in each of four public hospitals in Melbourne, Victoria, during the 2019 calendar year.

Main outcome measures

Discrepancy between the quantity of medication supplied and administered to patients (as proportion of medication supplied), overall and by hospital and ward type; direct cost to the hospitals of the discrepancies.

Results

The overall discrepancy rate (all medications, hospitals, ward types) was 19.2% (95% CI, 19.0–19.4%); overall rates by hospital ranged from 5.8% (95% CI, 5.7–5.9%) to 26.7% (95% CI, 26.6–26.9%). The discrepancies were largest for medications useful for self-treatment: oral antibiotics (eg, phenoxymethylpenicillin 250 mg capsule, 86.8%; 95% CI, 83.1–89.9%) and gastrointestinal medications (eg, ondansetron 4 mg tablet, 53.3%; 95% CI, 52.9–53.7%). Discrepancies were larger for oral than equivalent (or similar) parenteral formulations; they were generally low for controlled medications (temazepam, diazepam, oxycodone). Overall discrepancies were larger for EDs (32.3%; 95% CI, 32.2–32.5%) than for admitted patient wards, but differed between EDs (range: 25.7%; 95% CI, 25.5–26.0% to 39.5%; 95% CI, 39.2–39.7%). The estimated direct cost to hospitals of the discrepancies for the selected medications was $27 800.

Conclusion

Substantial quantities of medications supplied to hospital wards and EDs are not accounted for in electronic administration records.