Effects of gender, medical school class year, and majors on sleep quality in Chinese medical students: a systematic review and meta-analysis

Background Sleep problems are common in the general population, and medical students are one subgroup of the general population who appear to be especially vulnerable to poor sleep. This systematic review and meta-analysis examined the effects of gender, medical school class year, and majors on sleep quality among Chinese medical students. Methods Electronic databases, including PubMed, EMBASE, SCOPUS, Web of Science, Cochrane Library, WanFang, Chinese National Knowledge Infrastructure, and VIP Database were systematically searched from inception to 26 March 2019. Results Thirteen studies with 18,740 participants were included in the analysis. Among them, 25% of medical students exhibited poor sleep quality. No significant differences were found between male and female students in the prevalence of poor sleep quality (odds ratio = 0.87, 95% confidence interval 0.72, 1.04; Chi 2 = 3.88, I 2 = 0%) or Pittsburgh Sleep Quality Index scores (mean difference = − 0.06, 95% confidence interval − 0.15, 0.02; Chi 2 = 9.70, I 2 = 28%). No significant differences were found in the prevalence of poor sleep quality between students in lower and higher medical school class year (odds ratio = 0.98, 95% confidence interval 0.66, 1.45; Chi 2 = 38.84, I 2 = 83%). No significant differences were found in the prevalence of poor sleep quality (mean difference = 1.02, 95% confidence interval 0.77, 1.36; Chi 2 = 0.18, I 2 = 0%) or Pittsburgh Sleep Quality Index scores (mean difference = − 0.16, 95% confidence interval − 0.57, 0.26; Chi 2 = 0.99, I 2 = 0%) between students majoring in Clinical Medicine and Medical Imaging. Conclusions More detail is warranted in future studies in order to reveal subgroups of medical students who suffer from poor sleep quality.