No objective measures are available for assessing the practice of evidence-based medicine (EBM) in general practitioner (GP) trainees, as there is no description of the EBM behaviour that is expected from trainees. As a first step to do so, we aimed to identify which expressions of EBM (defined as the integration of evidence, clinical experience and patient situation) can be observed in daily GP practice. Secondly, we aimed to identify which considerations GPs had regarding EBM but did not share with the patient during consultations. We performed a qualitative study, in which GPs were observed during and interviewed after clinical consultations, with a focus on expressions and considerations related to EBM during clinical decision-making. We observed 147 consultations by 34 GPs (17 trainers and 17 trainees). EBM behaviour was rarely visible in GPs’ decision-making. When interviewing the GPs, we found that aspects of EBM that played a role in decision-making were not discussed with the patient. Explicit consideration of all aspects of EBM would make EBM measurable and GPs more aware of the foundations of their decisions. EBM behaviour is difficult to observe during GP consultations and therefore cannot be assessed through observations alone.