AimsThe aim of this meta-analysis is to examine the impact of ă in-hospital pharmacist-led medication reviews in paediatric and adult ă patients. ă MethodsRelevant studies were identified from the Medline and Cochrane ă Library databases. Studies were included if they met the following ă criteria (without any language or date restrictions): design: randomized ă controlled trial; intervention: in-hospital pharmacist-led medication ă review (experimental group) vs. usual care (control group); ă participants: paediatric or adult population. The primary outcome was ă all-cause readmissions and/or emergency department (ED) visits at ă different time points. The secondary outcomes were all-cause ă readmissions, all-cause ED visits, drug-related readmissions, mortality, ă length of hospital stay, adherence and quality of life. We calculated ă the relative risk (RR) or mean differences (MD) with 95% confidence ă intervals (CIs) for each study. We used fixed and/or random effects ă models. Heterogeneity was assessed using the I-2 statistic. ă ResultsWe systematically reviewed 19 randomized controlled trials (4805 ă participants). The readmission rates did not differ between the ă experimental group and the control group (RR=0.97, 95% CI 0.89; 1.05, ă p=0.470). The secondary outcomes did not differ between the two groups, ă except for in drug-related readmissions, which were lower in the ă experimental group (RR=0.25, 95% CI 0.14; 0.45, p<0.001), and all-cause ă ED visits (RR=0.70, 95% CI 0.59; 0.85 p=0.001). ă ConclusionThe low-quality evidence in this analysis suggests an impact ă of pharmacist-led medication reviews on drug-related readmissions and ă all-cause ED visits. Few studies reported on adherence and quality of ă life. More high-quality randomized clinical trials are needed to assess ă the impact of pharmacist-led medication reviews on patient-relevant ă outcomes, including adherence and quality of life.