OBJECTIVES: The aim of this study was to determine how the medical performance of physicians during consultations is related to doctor-patient communication and satisfaction of patients, taking into account the actual length of the consultations. In addition, we studied the validity of the 'efficiency-per-time score' as a measure of competence. METHODS: General practice trainees participated in a test situation in which they were confronted with six consultations with standardized (simulated) patients (SPs). All consultations were videotaped and evaluated by multiple observers, using national guidelines on medical content and on communication. The SPs scored satisfaction with the consultation using a satisfaction checklist. Forty GP-trainees were invited, of whom 34 participated. The main outcome measures were the number of obligatory actions undertaken by the GP-trainees, total number of actions undertaken, consultation time, efficiency-per-time score, patient satisfaction and quality of communication score, and the Pearson correlations between these measures. RESULTS: There was a negative correlation between the 'efficiency-per-time score' of the GP-trainees and the satisfaction of the SPs in five of the six consultations [Pearson r from -0.29 (P < 0.05) to -0.58 (P < 0.001)] and between the 'efficiency-per-time score' and the quality of the communication in three of the six consultations [Pearson r from -0.34 (P <.05) to -0.51 (P < 0.001)]. CONCLUSIONS: Short consultations with high technical medical efficiency seem to be related to bad communication and dissatisfied patients, thus questioning the validity of the 'efficiency-per-time score' as a measure of competence.