AIM: In a problem-based learning (PBL) curriculum, tutor's feedback skills are important. However, evaluation studies often show that students rate many tutors as ineffective in providing feedback. We explored whether this is related: (a) to tutors' skills, and hence a teaching intervention might improve their performance; (b) to the formulation of the evaluation item, hence a more specific wording might help students better recognize a feedback when received; (c) to PBL teaching environment, and hence the tutors' teaching unit might influence students' ratings. METHODS: Students rated 126 tutors of 13 one-month teaching units over three consecutive years on their ability of providing feedback. We assessed how (a) a teaching intervention given between years 1 and 2, (b) a rewording of the evaluation item which took place in year 3, and (c) the tutors' teaching unit, influenced students' ratings. RESULTS: The ratings of tutors considered as effective by students at year 1 improved after the teaching intervention, while those of unsatisfactory tutors did not progress. However the ratings of the latter increased after reformulation of the evaluation item. This increase varied across teaching units. DISCUSSION: Students' ratings of tutors' ability to give feedback seem to vary in function of the tutors' training, of the formulation of the evaluation item, and of the tutors' teaching environment. These variables should be considered for setting up effective strategies in faculty development.