ObjectiveVerbal face-to-face feedback on clinical task performance is a fundamental component of health professions education. Experts argue that feedback is critical for performance improvement, but the evidence is limited. The aim of this systematic review was to investigate the effect of face-to-face verbal feedback from a health professional, compared with alternative or no feedback, on the objective workplace task performance of another health professional.DesignSystematic review and meta-analysis.MethodsWe searched the full holdings of Ovid MEDLINE, CENTRAL, Embase, CINAHL and PsycINFO up to 1 February 2019 and searched references of included studies. Two authors independently undertook study selection, data extraction and quality appraisal. Studies were included if they were randomised controlled trials investigating the effect of feedback, in which health professionals were randomised to individual verbal face-to-face feedback compared with no feedback or alternative feedback and available as full-text publications in English. The certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations approach. For feedback compared with no feedback, outcome data from included studies were pooled using a random effects model.ResultsIn total, 26 trials met the inclusion criteria, involving 2307 participants. For the effect of verbal face-to-face feedback on performance compared with no feedback, when studies at high risk of bias were excluded, eight studies involving 392 health professionals were included in a meta-analysis: the standardised mean difference (SMD) was 0.7 (95% CI 0.37 to 1.03; p<0.001) in favour of feedback. The calculated SMD prediction interval was −0.06 to 1.46. For feedback compared with alternative feedback, studies could not be pooled due to substantial design and intervention heterogeneity. All included studies were summarised, and key factors likely to influence performance were identified including components within feedback interventions, instruction and practice opportunities.ConclusionsVerbal face-to-face feedback in the health professions may result in a moderate to large improvement in workplace task performance, compared with no feedback. However, the quality of evidence was low, primarily due to risk of bias and publication bias. Further research is needed. In particular, we found a lack of high-quality trials that clearly reported key components likely to influence performance.Trial registration numberCRD42017081796.