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<div><p>Objective</p><p>This study aimed to comprehensively evaluate the effect of PBL on problem-solving, self-directed learning, and critical thinking ability of pharmaceutical students through a randomized controlled trial (RCT) and meta-analysis of RCTs.</p><p>Methods</p><p>In 2021, 57 third-year pharmacy students from China Pharmaceutical University were randomly divided into a PBL group and a lecture-based learning (LBL) group. Mean scores were compared between the two groups for problem-solving, self-directed learning, communication skills, critical thinking, and final exam grades. Students’ feedback on the implementation of PBL was also collected. A meta-analysis was subsequently performed. Two authors independently conducted a comprehensive search of two databases (PubMed and CNKI). Eligible studies with effective data were included and the valuable data were extracted for analysis. Quality of involved studies was assessed by the Cochrane Collaboration’s tool. All analyses of statistics were conducted using the ‘metafor’ package in R software.</p><p>Results</p><p>The PBL group had significantly higher mean scores for problem-solving (8.43±1.56) and self-directed learning (7.39±1.19) than the LBL group (7.02±1.72 and 6.41±1.28, respectively). The PBL group also showed better communication skills (8.86±1.47) than the LBL group (7.68±1.89). The mean level of critical thinking was significantly higher in the PBL group than the LBL group (p = 0.02). The PBL group also had better final exam grades (79.86±1.38) compared to the LBL group (68.1±1.76). Student feedback on PBL implementation was positive. The outcome of subsequent meta-analysis including 8 eligible studies involved 1819 participants showed that the use of PBL significantly improved problem-solving ability (SMD = 1.12, 95% CI = 0.25–1.99) and PBL was also associated with better performance in self-directed learning (SMD = 1.55, 95% CI = 0.64–2.45). However, there was no significant difference in the final exam score in the PBL group compared to the LBL control group (SMD = 0.23, 95% CI = -0.08–0.53).</p><p>Conclusion</p><p>This study found that PBL is an effective teaching method for pharmacy students.</p></div>