Validation of the 5-item doctor-patient communication competency instrument for medical students (DPCC-MS) using two years of assessment data

BACKGROUND Medical students on clinical rotations have to be assessed on several competencies at the end of each clinical rotation, pointing to the need for short, reliable, and valid assessment instruments of each competency. Doctor patient communication is a central competency targeted by medical schools however, there are no published short (i.e. less than 10 items), reliable and valid instruments to assess doctor-patient communication competency. The Faculty of Medicine of Laval University recently developed a 5-item Doctor-Patient Communication Competency instrument for Medical Students (DPCC-MS), based on the Patient Centered Clinical Method conceptual framework, which provides a global summative end-of-rotation assessment of doctor-patient communication. We conducted a psychometric validation of this instrument and present validity evidence based on the response process, internal structure and relation to other variables using two years of assessment data. METHODS We conducted the study in two phases. In phase 1, we drew on 4991 student DPCC-MS assessments (two years). We conducted descriptive statistics, a confirmatory factor analysis (CFA), and tested the correlation between the DPCC-MS and the Multiple Mini Interviews (MMI) scores. In phase 2, eleven clinical teachers assessed the performance of 35 medical students in an objective structured clinical examination station using the DPCC-MS, a 15-item instrument developed by Côté et al. (published in 2001), and a 2-item global assessment. We compared the DPCC-MS to the longer Côté et al. instrument based on internal consistency, coefficient of variation, convergent validity, and inter-rater reliability. RESULTS Phase 1: Cronbach's alpha was acceptable (.75 and .83). Inter-item correlations were positive and the discrimination index was above .30 for all items. CFA supported a unidimensional structure. DPCC-MS and MMI scores were correlated. Phase 2: The DPCC-MS and the Côté et al. instrument had similar internal consistency and convergent validity, but the DPCC-MS had better inter-rater reliability (mean ICC = .61). CONCLUSIONS The DPCC-MS provides an internally consistent and valid assessment of medical students' communication with patients.