Prevalence and characteristics of medication errors at the outpatient settings, Jigme Dorji Wangchuck National Referral Hospital (JDWNRH): Retrospective study.

Technical Summary: Prevalence and Characteristics of Medication Errors at the Outpatient Settings, JDWNRH

Problem Statement
Medication errors (MEs) are a significant threat to patient safety, accounting for approximately one-quarter of all healthcare-associated errors. While the prevalence of MEs is well-documented in inpatient settings, there is a scarcity of data regarding their prevalence and characteristics in outpatient environments, particularly within low-and-middle-income countries (LMICs). Without specific data on the nature and frequency of errors in these settings, targeted interventions cannot be effectively contextualized. This study addresses this gap by analyzing medication errors at the outpatient department of Jigme Dorji Wangchuck National Referral Hospital (JDWNRH) in Bhutan.

Methodology
The study employed a retrospective analytical design, reviewing data collected between November 1, 2024, and September 30, 2025. The data source was the Pharmaceutical Care Intervention Unit (PCIU) at JDWNRH, established in August 2024 to monitor outpatient prescriptions.

• Data Collection: All outpatient prescriptions generated via the electronic Patient Information System (ePIS) were reviewed by hospital pharmacists for appropriateness regarding indications, dose, frequency, duration, drug-drug interactions, and adverse drug reactions (ADRs).
• Intervention Protocol: When a prescribing error was identified, the designated pharmacist contacted the prescriber via telephone to request amendments. The unit also recorded packaging errors (wrong medicine in the dispensing envelope) identified by dispensers and dispensing errors (wrong medicine dispensed and returned by patients).
• Classification: Errors were categorized into prescribing, packaging, and dispensing errors. Prescribing errors included issues such as wrong dose, wrong frequency, no indication, omission, and drug interactions.
• Harm Assessment: The potential severity of harm was classified using the Harm Associated with Medication Error Classification (HAMEC) tool into four levels: No harm, Minor, Moderate, and Serious. Actual harm was defined as errors that reached the patient.
• Standards: Compliance was assessed against national guidelines (e.g., National Antibiotic Guidelines-2018, National Essential Medicine Formulary-2022) and international references (e.g., BNF, UpToDate, IDSA).

Key Results
Out of 90,108 prescriptions dispensed during the study period, 2,045 (2.27%) were recorded with at least one type of medication error.

• Error Distribution: Prescribing errors were the most prevalent, accounting for 90.81% (n=1,857) of all errors. Packaging errors constituted 8.70% (n=178), and dispensing errors accounted for 0.49% (n=10).
• Therapeutic Categories: More than half of the prescribing errors involved antibiotics (39.3%) and antihypertensives (13.9%).
• Error Types: The most common prescribing error was "wrong dose" (63.5%), followed by "wrong frequency" (12.0%), "no indication" (10.0%), and "omission" (5.7%).
• Prescriber Demographics: Specialists (52%) and General Duty Medical Officers (27.1%) were the primary sources of prescribing errors. The General Outpatient Department (28.7%) and the Medical Department (24.2%) were the most affected units.
• Severity and Intervention:
  • Potential Harm: The majority of prescribing errors (73.45%) were classified as having "moderate" potential harm.
  • Intervention Success: Pharmacist-led interventions successfully prevented 93.32% (1,733 out of 1,857) of prescribing errors from reaching patients.
  • Actual Harm: Only 6.68% of prescribing errors reached the patient. Among serious errors (n=48), 8.33% reached the patient, primarily involving anticoagulants and antiepileptics.
  • Packaging/Dispensing: All packaging errors were intercepted before reaching patients. However, 100% of the recorded dispensing errors reached the patients, with antihypertensives being the most common category.

Significance and Claims
The authors claim this study provides the first baseline data on the prevalence and characteristics of medication errors in the outpatient setting at JDWNRH. The study highlights that while the overall prevalence of MEs (2.27%) is relatively low compared to some international reports, prescribing errors remain the dominant issue, specifically regarding dosing in antibiotic and antihypertensive therapies.

The paper emphasizes the critical role of pharmacist-led interventions, noting that these interventions prevented over 90% of potential harm associated with prescribing errors. The authors conclude that integrating pharmacists effectively into disease management systems is essential for enhancing patient safety. They further suggest that targeted training for prescribers, particularly in the therapeutic management of infectious diseases and hypertension, is necessary to minimize prescribing errors.

Limitations
The authors acknowledge that the study did not capture patient demographic or clinical characteristics, limiting the ability to assess specific factors contributing to errors. Additionally, the reliance on active reporting for packaging and dispensing errors may have led to under-reporting, as patients may not always report errors encountered at home. The study is a preprint and has not yet undergone peer review.