Aims Prescribing errors occur frequently, especially among junior doctors. Our aim was to investigate prescribing errors made by final‐year medical students. Information on these errors can help to improve education on and assessment of clinical pharmacotherapy (CPT). Methods This was a retrospective cohort study amongst final‐year medical students at Erasmus Medical Centre, The Netherlands. Errors made in the final prescribing assessment were analysed. Errors were categorized by type, possible consequence and possibility of reaching the patient in real life. Results A total of 381 students wrote 1502 analysable prescriptions. Forty per cent of these contained at least one error, and 54% of errors were of the inadequate information type. The rating of prescriptions for children was lower than for other question categories (P = <.001). Fifty per cent of errors were classified as “would have reached the patient but would not have had the potential to cause harm”. In total, 253 (29%) errors would not have been intercepted by an electronic prescribing system or a pharmacist. Ten (4%) of these would probably have caused harm in the patient. Conclusions There is a high rate of errors in prescriptions written by final‐year medical students. Most errors were of the inadequate information type, indicating that students had difficulties determining the content and amount of information needed to make treatment successful. Prescriptions for children contained most errors. Curricula could be improved by offering more case‐based CPT education, focusing on the practical issues of prescribing, especially for paediatric cases, and offering more practice time for prescribing during clerkships.

Purpose Formative assessments can help motivate students and ease students’ learning through feedback. There is a pressing need for improvement of clinical pharmacotherapy (CPT) education since junior doctors make many prescribing errors. The aim of this study was to determine whether a formative assessment with personalized narrative feedback helps medical students to increase their prescribing skills. Methods This retrospective cohort study was conducted among masters’ medical students at Erasmus Medical Centre, The Netherlands. Students made a formative and a summative skill-based prescription assessment, both during clerkships as part of their regular curriculum. Errors in both assessments were categorized by type and possible consequence and compared with each other. Results A total of 388 students made 1964 errors in the formative assessment and 1016 in the summative assessment. Most improvements after the formative assessment were seen for mentioning the weight of a child on the prescription (n = 242, 19%). Most new and repeated errors in the summative assessment were missing usage instructions (n = 82, 16% and n = 121, 41%). Conclusions This formative assessment with personalized and individual narrative feedback has helped students to increase the technical correctness of their prescriptions. However, errors repeated after the feedback were predominantly errors showing that only one formative assessment has not yet enhanced the clinical prescribing enough.