RESUMO
BACKGROUND: Medical schools have used mindfulness meditation as a strategy to assist students in stress management. This study aimed to seek evidence regarding the effectiveness of mindfulness-based training programs in reducing psychological distress and promoting the well-being of medical students. METHODS: We conducted a systematic review and meta-analysis. Cochrane Library, Embase, PubMed/MEDLINE, PsycINFO/PsycNet, LILACS/BVS, ERIC (ProQuest), Web of Science, OpenGrey, and Google Scholar were searched for randomized clinical trials published until March 2022, without time or language restrictions. Two authors independently screened the articles, extracted data using a standardized extraction form, and assessed the methodological quality of the included studies using the Cochrane's Risk of Bias 2 (ROB 2) tool and the quality of evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool. RESULTS: Of the 848 articles retrieved, 8 met the inclusion criteria. Mindfulness-based training improved the outcomes: mindfulness (small post-intervention effect: SMD = 0.29; 95% CI: 0.03 to 0.54; p = 0.03; I2 = 46%; high evidence quality, and small effect at follow-up: SMD = 0.37; 95% CI: 0.04 to 0.70; p = 0.03; I2 = 53%; low evidence quality), psychological well-being/health (there was no statistically significant difference between the groups in the post-intervention effect: SMD = - 0.27; 95% CI: - 0.67 to 0.13; p = 0.18; I2 = 76%; moderate evidence quality, and a significant difference at follow-up: SMD = - 0.73; 95% CI: - 1.23 to - 0.23; p = 0.004; I2 = 61%; low evidence quality), and stress (small post-intervention effect: SMD = - 0.29; CI of 95%: - 0.56 to - 0.02; p = 0.04; I2 = 57%; moderate evidence quality, and moderate effect at follow-up: SMD = - 0.45, 95% CI: - 0.67 to - 0.22, p = 0.0001, I2 = 0%, moderate evidence quality). The quality of evidence for the anxiety, depression, and resilience outcomes is low and for the empathy outcome, very low. CONCLUSION: The results indicate that the students who participated in the mindfulness training perceived improvements in the stress and psychological distress symptoms and improved health perception and psychological well-being. However, the significant heterogeneity among studies should be considered when interpreting these findings. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42020153169.