The development of appropriate communication skills by healthcare providers is central to providing quality patient-centred care. Patients can provide valuable feedback to practitioners about their clinical communication. However, in oral health care, their involvement is uncommon and instruments specific for communication in oral health care have not been available. Recently, two complementary instruments have been developed by the Faculty of Dentistry, University of Manitoba for evaluating student-clinicians' clinical communication: one for patient evaluation and one for student self-evaluation. The aim of the current study was to provide validity evidence for the scores related to the internal structure of the revised 2007 versions of these instruments in two dental clinical/education contexts, namely the Universities of Manitoba, Canada (UM) and Adelaide, Australia (UA). The proposed factor structure and loadings, and their stability across contexts were assessed using confirmatory factor analysis, and the adequacy of the internal consistency reliability of the scores was analysed using Cronbach's alpha. The factor structure of the current 2007 versions of the patient and student instruments, derived from the previously developed longer versions of these instruments, was confirmed and was consistent across the two clinical/educational contexts. A model of partial invariance provided the best fit for these data due to variations in the magnitude of the factor loadings between sites. The internal consistency reliability of scores was high with a range of 0.88–0.97. In conclusion, the current study provides preliminary evidence regarding the validity of the scores of the current 2007 instruments, in terms of the internal structure, as measuring the five factors well. Replication of the factor structure of these instrument scores with more participants at both UA and other institutions is required.