Safety incidents associated with extended working hours. A systematic review and meta-analysis

• Main Authors: Dagfinn Matre (Author), Marit Skogstad (Author), Tom Sterud (Author), Karl-Christian Nordby (Author), Stein Knardahl (Author), Jan Olav Christensen (Author), Jenny-Anne S Lie (Author)
• Format: Book
• Published: Nordic Association of Occupational Safety and Health (NOROSH), 2021-09-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 0355-3140; 1795-990X; 10.5271/sjweh.3958
• Keywords: long work week; occupational injury; meta-analysis; safety; accident; overtime; systematic review; injury; long working time; extended working hour; safety-related incident; safety incident; near accident; Public aspects of medicine; RA1-1270
• Source: Scandinavian Journal of Work, Environment & Health, Vol 47, Iss 6, Pp 415-424 (2021)

OBJECTIVE: We performed a systematic review to assess potential consequences of extended working hours on accidents, near-accidents, safety incidents and injuries (incidents) by considering the overall certainty of evidence. METHODS: We searched five databases systematically (Medline, Embase, PsycINFO, Web of Science, and Proquest Health and safety Science Abstract) and identified 10072 studies published until December 2020. Twenty-two studies met the inclusion criteria. We followed a systematic approach to evaluate risk of bias and synthesize results in a meta-analysis. The certainty of evidence was determined by a modified version of The Grading of Recommendations Assessment, Development and Evaluation (GRADE). RESULTS: Our analyses indicated an association between working >12 hours/day (RR: 1.24, 95%CI: 1.11, 1.40), or working >55 hours/week (RR: 1.24, 95%CI: 0.98, 1.57), and elevated risk of incidents. The certainty of evidence evaluated as low. Weak or no associations were observed for other exposure contrasts: working >8 hours/day (RR: 0.93, 95%CI: 0.72, 1.19), or working overtime (RR: 1.08, 95%CI: 0.75, 1.55), working 41-48 hours/week (RR: 1.02, 95%CI: 0.92, 1.13) or 49-54 hours/week (RR: 1.02, 95%CI: 0.97, 1.07). The certainty of evidence was evaluated as low (very low for 41-48 hours/week). CONCLUSIONS: Daily working hours >12 hours and weekly working hours exceeding 55 hours was associated and increased risk of incidents. The level of evidence was low. Hence, further high-quality research is warranted to elucidate these associations.