OBJECTIVE: To examine students’ attitudes and potential behaviour towards informing a 12-year-old patient of her terminal prognosis in a situation in which her parents do not wish her to be told, as they pass through a modern medical curriculum. DESIGN: A cohort study of students entering Glasgow University’s new medical curriculum in October 1996. METHODS: Students’ responses obtained before year 1 and at the end of years 1, 3, and 5 to the "childhood leukaemia" vignette of the Ethics in Health Care Survey Instrument (EHCI) were examined quantitatively and qualitatively. Analysis of the students’ multichoice answers enabled measurement of the movement towards professional consensus opinion. An analysis of their written justifications for their answers helped to determine whether their reasoning was consistent with professional consensus and enabled measurement of changes in knowledge content and recognition of the values inherent in the vignette. Themes on the students’ reasoning behind their decision to tell the patient or not were also identified. RESULTS: Unlike other vignettes of the EHCI in which autonomy was a main theme, few students chose the consensus answer before year 1 and there was no significant movement towards consensus at any point during the course. In defence of their decision to withhold information, the students expressed strong paternalistic opinions. The patient’s age was seen as a barrier to respecting her autonomy. CONCLUSIONS: It is important to identify students’ perceptions on entry to medical school. Transformative learning theory may provide the basis for an approach to foster doctors who consider the rights of young people. Small-group teaching is most conducive to this approach. The importance of positive role modelling is also emphasised.