Introduction 1 2 Guide to Good Prescribing 3 4 Guide to Good Prescribing p p 5 p 4 p p Therefore, the aim of this study was to determine whether there is a difference in prescribing skills between medical students who have been trained in creating and using a personal formulary and those who have been trained in using existing formularies only. Materials and methods Study design 1 Fig. 1  PF  EF  C  A  B  C  D  1  2  3  4  After the posttest, a structured questionnaire with 21 questions was administered to identify differences in the type of teaching students received prior to the study. The questions were about two major teaching issues: curriculum type; and teaching methods in pharmacology, clinical pharmacology and pharmacotherapy. Other questions were designed to verify whether the universities had carried out the study in full accordance with the standard protocol. The study was approved by the educational research committee of the VU University Medical Center (VUMC). Study population Six hundred and nine undergraduate medical students from eight countries were selected on a voluntary basis (Vellore in India, Yogyakarta in Indonesia, Maastricht in the Netherlands, Kazan in the Russian Federation, Bratislava in Slovakia, Cape Town in South Africa, La Laguna in Spain and Aden/Sana’a (jointly) in Yemen). All students had passed their pharmacology examinations (basic pharmacology and clinical pharmacology) and were about to start their clinical internships. Participation in the study was in addition to their normal curriculum. All students were informed in advance about the general aim of the study and the method of testing. Cross-contamination of the students in the study groups and the control group was prevented by giving the students in the control group the opportunity to participate in a training programme after the study. Materials 1 General patient information (e.g. age, gender, allergy, occupation and pregnancy) Summary of previous and current diseases and treatments (comorbidity and comedication) Extensive description of the present history and a physical examination Diagnosis 6 Guide to Good Prescribing p 7 Intervention 1 4 8 p p Test and scoring 1 Statistical analysis p Results 1 1 Table 1 Pre- and posttest scores per university   Nujmber Pretest Posttest PF EF C PF EF C Yemen 73 0.41 0.35 0.33 ab b 0.46 Russia 88 0.83 0.91 0.87 ab b 1.03 Indonesia 75 1.12 1.20 1.34 ab b 1.42 Netherlands 64 2.20 2.06 2.25 b b c Slovakia 72 2.27 2.13 2.12 3.20 3.12 c India 72 2.17 2.39 2.23 2.19 b 2.08 Spain 73 2.38 2.33 2.28 2.61 b 2.36 South Africa 66 2.54 2.48 2.38 3.02 2.97 c All Increase 583 1.71 1.62 1.69 a,b b c PF  EF  C a p b p c p 1 2 Fig. 2  PF  EF  C  # = PF > EF  The results of the questionnaire about the type of teaching that students received indicated that Yemen, the Russian Federation and Indonesia had a predominantly classic curriculum. On average, the participating students from these universities had received 90 h (range 52–160 h) of pharmacology teaching by lectures, 23 h (range 3–50 h) of clinical pharmacology teaching also by lectures and no explicit pharmacotherapy teaching. These students were not familiar with PBL but were somewhat accustomed to discussion in small groups. The remaining five universities had a predominantly problem-based teaching curriculum. The participants had received an average of 43 h (range 6–100 h) of pharmacology teaching by lectures, including small group teaching; 24 h (range 6–40 h) of clinical pharmacology teaching, mainly by small group teaching; and no explicit pharmacotherapy teaching. The students from these universities were all familiar with PBL and were all accustomed to discussion in small groups. Some of these students already had some clinical experience (Slovakia and Spain). Except for the presence (or absence) of PBL, no other differences in teaching could be identified between any of the eight universities. No specific differences between universities in the way the study was performed or indications for possible bias were identified. Discussion  p 4 An important question is why these five universities had such high initial scores? The questionnaire was specifically designed for the purpose of this study, and the only explanation that emerged was that students from these five universities had received problem-based teaching and were therefore familiar with the process of solving patient problems. In the universities with lower pretest scores, classic teaching was paramount and students had less experience with solving patient problems. 9 10 p The limitations of our study need to be addressed. The voluntary participation of students may have created a positive bias for the total group, but allocation to the intervention groups was randomised and therefore the comparison was unbiased. In addition, to ensure baseline comparability among the groups, previous results on university examinations were averaged for the three groups. The scoring by the medical schools was blinded, with the pre- and posttest forms of all three groups being mixed during the scoring. Cross-contamination between the study and control groups was prevented by explaining to the students the importance of not exchanging any information and by reassuring the control group that it would receive the training after finishing the study. Therefore, taking the above-mentioned limitations and considerations into account, it can be concluded that training in developing and using a personal formulary or in the use of an existing formulary may increase the rational prescribing of medical students. However, with regard to universities with a general problem-based curriculum, training in the development of a personal formulary is probably not worth the additional effort. In these circumstances, pharmacotherapy teaching can be based on existing formularies instead of a personal formulary. 11 12 13 14