Effect of rater training on reliability and accuracy of mini-CEX scores: A randomized, controlled trial

BACKGROUND: Mini-CEX scores assess resident competence. Rater training might improve mini-CEX score interrater reliability, but evidence is lacking. OBJECTIVE: Evaluate a rater training workshop using interrater reliability and accuracy. DESIGN: Randomized trial (immediate versus delayed workshop) and single-group pre/post study (randomized groups combined). SETTING: Academic medical center. PARTICIPANTS: Fifty-two internal medicine clinic preceptors (31 randomized and 21 additional workshop attendees). INTERVENTION: The workshop included rater error training, performance dimension training, behavioral observation training, and frame of reference training using lecture, video, and facilitated discussion. Delayed group received no intervention until after posttest. MEASUREMENTS: Mini-CEX ratings at baseline (just before workshop for workshop group), and four weeks later using videotaped resident-patient encounters; mini-CEX ratings of live resident-patient encounters one year preceding and one year following the workshop; rater confidence using mini-CEX. RESULTS: Among 31 randomized participants, interrater reliabilities in the delayed group (baseline intraclass correlation coefficient [ICC] 0.43, follow-up 0.53) and workshop group (baseline 0.40, follow-up 0.43) were not significantly different (p = 0.19). Mean ratings were similar at baseline (delayed 4.9 [95% confidence interval 4.6-5.2], workshop 4.8 [4.5-5.1]) and follow-up (delayed 5.4 [5.0-5.7], workshop 5.3 [5.0-5.6]; p = 0.88 for interaction). For the entire cohort, rater confidence (1 = not confident, 6 = very confident) improved from mean (SD) 3.8 (1.4) to 4.4 (1.0), p = 0.018. Interrater reliability for ratings of live encounters (entire cohort) was higher after the workshop (ICC 0.34) than before (ICC 0.18) but the standard error of measurement was similar for both periods. CONCLUSIONS: Rater training did not improve interrater reliability or accuracy of mini-CEX scores. CLINICAL TRIALS REGISTRATION: clinicaltrials.gov identifier NCT00667940.