BackgroundExisting handover communication tools often lack a clear theoretical foundation, have limited psychometric evidence, and overlook effective communication strategies for enhancing diagnostic reasoning. This oversight becomes critical as communication breakdowns during handovers have been implicated in poor patient care. To address these issues, we developed a structured communication tool: Background, Responsible diagnosis, Included differential diagnosis, Excluded differential diagnosis, Follow-up, and Communication (BRIEF-C). It is informed by cognitive bias theory, shows evidence of reliability and validity of its scores, and includes strategies for actively sending and receiving information in medical handovers.DesignA pre–test post-test intervention study.SettingInpatient internal medicine and orthopaedic surgery units at one tertiary care hospital.InterventionThe BRIEF-C tool was presented to internal medicine and orthopaedic surgery faculty and residents who participated in an in-person educational session, followed by a 2-week period where they practised using it with feedback.MeasurementsClinical handovers were audiorecorded over 1 week for the pre- and again for the post-periods, then transcribed for analysis. Two faculty raters from internal medicine and orthopaedic surgery scored the transcripts of handovers using the BRIEF-C framework. The two raters were blinded to the time periods.ResultsA principal component analysis identified two subscales on the BRIEF-C: diagnostic clinical reasoning and communication, with high interitem consistency (Cronbach’s alpha of 0.82 and 0.99, respectively). One sample t-test indicated significant improvement in diagnostic clinical reasoning (pre-test: M=0.97, SD=0.50; post-test: M=1.31, SD=0.64; t(64)=4.26, p<0.05, medium to large Cohen’s d=0.63) and communication (pre-test: M=0.02, SD=0.16; post-test: M=0.48, SD=0.83); t(64)=4.52, p<0.05, large Cohen’s d=0.83).ConclusionThis study demonstrates evidence supporting the reliability and validity of scores on the BRIEF-C as good indicators of diagnostic clinical reasoning and communication shared during handovers.