Receiving feedback from different types of assessors (e.g., senior residents, staff supervisors) may impact trainees' perceptions of the quantity and quality of data during entrustable professional activity (EPA) assessments. We evaluated the quality of EPA feedback provided by different assessors (senior residents, chief medical residents/subspecialty residents, and staff) and explored residents' judgements of the value of this feedback. From a database of 2228 EPAs, we calculated the frequency of contribution from three assessor groups. We appraised the quality of 60 procedure-related EPAs completed between July 2019 and March 2020 using a modified Completed Clinical Evaluation Report Rating (CCERR) tool. Next, we asked 15 internal medicine residents to sort randomly selected EPAs according to their judgements of value, as an elicitation exercise before a semi-structured interview. Interviews explored participants' perceptions of quality of written feedback and helpful assessors. Residents completed over 60% of EPA assessments. We found no difference in modified-CCERR scores between the three groups. When judging EPA feedback value, residents described a process of weighted deliberation, considering perceived assessor characteristics (e.g., credibility, experience with EPA system), actionable written comments, and their own self-assessment. Like other recent studies, we found that residents contributed most to procedure-related EPA assessments. To the established list of factors influencing residents' judgements of feedback value, we add assessors' adherence to, and their shared experiences of being assessed within, EPA assessment systems. We focus on the implications for how assessors and leaders can build credibility in themselves and in the practices of EPA assessments.