he quantity of a medication supplied to a hospital ward should closely match the quantity administered to patients. 1 A discrepancy between the amounts supplied and used may reflect medication expiry, wastage, after-hours transfer to other wards, failure to document administration, or theft. 2 In emergency department (EDs), discrepancies have been reported for medications commonly used for self-treatment, and for oral alternatives to parenteral preparations. 1 Unlawful diversion of controlled medications is also a recognised problem. [3][4][5][6][7][8][9] Evaluating medication discrepancies was difficult when records were paper-based, as collating administrative data required a labour-intensive medical record audit. Electronic medication records, including medication supply and administration data, have facilitated the detection of medication discrepancies. 1 In this study, we analysed electronic medication supply and administration data for a variety of inpatient wards and EDs. Our aim was to describe the nature, extent, and cost of medication discrepancies.
MethodsWe undertook a multicentre, retrospective observational study in the Austin, Box Hill, Footscray, and Frankston Hospitals in Melbourne, Victoria. The four hospitals are public metropolitan teaching centres with 560, 300, 425, and 401 beds respectively, and their EDs received 90 000, 43 200, 64 604, and 100 616 people in 2019 (according to hospital records).We assessed the quantities of selected medications supplied to two general medical wards, two surgical wards (one general, one orthopaedic) and the ED of each hospital, and the amounts administered to patients during the 2019 calendar year. Medication supply data were extracted from the pharmacy drug management system (MERLIN, PharmHos or iPharmacy, iSoft), and medication administration data from the electronic prescribing system (Millennium, Cerner). Data on doses that were lost, wasted, returned to the pharmacy, or destroyed were not available.For this study, an emergency physician and senior hospital pharmacists purposively sampled medications that are frequently prescribed (eg, for simple analgesia), useful for selftreatment (eg, anti-emetics), are associated with illegal diversion (eg, benzodiazepines), and oral and parenteral preparations of the same or similar medications (eg, oral and parenteral ondansetron). The selection was informed by the results of a pilot study, 1 and was not influenced by medication cost:• Antibiotics ► Phenoxymethylpenicillin (250 mg capsule), benzylpenicillin (1.2 g injection)► Cefalexin (500 mg capsule), ceftriaxone (1 g vial)