MATERIALS AND METHODS: This retrospective comparative analysis examines inpatient prescription data collected from the same hospital wards during three distinct periods: 1st January to 31st March 2023 (59,663 handwritten prescriptions), 1st October to 31st December 2023 (43,363 electronic prescriptions at 3 months post-CPOE implementation) and 1st January to 31st March 2024 (44,317 electronic prescriptions at 6 months post-CPOE implementation). The CPOE system was implemented in July 2023.

RESULTS: The CPOE system significantly reduced medication prescribing errors (3 months post-CPOE: n=832, 1.92%; 6 months post-CPOE: n=617, 1.39%) compared to handwritten prescriptions (n=3532, 5.92%). The odds of errors occurring 3 months and 6 months post-CPOE implementation were 65% and 75% lower, respectively, than during the handwritten phase [Odds Ratio (OR), 0.35; 95% Confidence Interval (CI), 0.32 - 0.38] and [OR, 0.25; 95% CI, 0.23 - 0.28]. Potential error sources associated with handwritten prescriptions, such as illegible prescriptions, non-standard abbreviations and incomplete prescriptions, were entirely eliminated with CPOE adoption. Significant differences in error types were observed between handwritten and electronic prescriptions (p<0.001). However, errors related to incorrect dosage, frequency and unit of measurement increased under the CPOE system compared to handwritten prescriptions (p<0.001). A significant reduction in odds occurred with wrong unit of measurement [OR, 0.61; 95% CI, 0.52 - 0.72) followed by frequency errors [OR, 0.58; 95% CI, 0.47 - 0.73) from the 3 months to 6 months post-CPOE implementation. Non-significant reductions or increments in odds were observed for other error types including wrong dosage, wrong route, wrong form, wrong strength and wrong or inappropriate drugs between the two 3-month post-CPOE periods.