Objective: To systematically evaluate the association between different types of environmental noise, particularly traffic noise, and sleep disturbances; to quantify the effect size and to explore key factors contributing to heterogeneity, thereby providing evidence to inform noise control and public health interventions. Methods: Publications from 2005 to 2025 were systematically searched in PubMed, Embase, Cochrane Library and Web of Science. A total of 68 observational studies were included in accordance with preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Random-effects models were applied to pool effect sizes (correlation coefficients, r ). Subgroup analyses, meta-regression, sensitivity analyses and Egger’s test were conducted to explore sources of heterogeneity and publication bias. The certainty of evidence was assessed using the grading of recommendations assessment, development and evaluation (GRADE) framework. Results: Exposure to traffic noise was significantly associated with sleep disturbances. Source-specific analyses indicated that aircraft noise ( r = 0.26) and railway noise ( r = 0.21) were associated with larger effect sizes than road traffic noise ( r = 0.15). Subgroup and meta-regression analyses identified outcome assessment methods, study design and geographic region as the main contributors to between-study heterogeneity. Evidence related to non-traffic noise was limited; however, available data suggested that community and hospital noise may also adversely affect sleep. Sensitivity analyses and assessments of publication bias indicated that the pooled estimates were robust. According to the GRADE framework, the overall certainty of evidence was rated as high. Conclusions: Environmental noise, particularly traffic noise, significantly increases the risk of sleep disturbances. Type-specific effects were observed, and a dose–response relationship was also identified. These findings support the need for further reductions in nighttime traffic noise exposure and strengthened residential noise control to promote population sleep health.
Zitong Li (Sun,) studied this question.