Figure 2.

Meta analysis studies on circadian disruption and cancer incidence. The studies analyzed by Dun et al. (34) met the following criteria: (1) night-shift work was reported; (2) cancer risk was investigated; (3) cohort studies, case-control studies, or nested case-control studies; (4) the risk was estimated by odds ratio (OR), risk ratio, or hazard ratio, with 95% confidence interval (CI). Cancer risks among individuals with different classifications of night work duration (0–5, 6–10, 11–15, 16–20, 21–25, and ≥26 years) are plotted. Taking all eligible studies together, night-shift work did not increase the risk of cancer in any group of night workers. Image modified with permission from Ref.34 and used under Creative Commons.