A Cochrane review included 13 interrupted time series studies. Seven studies evaluated the effect of regulations, two evaluated a safety campaign, one evaluated a drug-free workplace programme, one evaluated a training programme and one evaluated safety inspections on fatal and non-fatal occupational injuries. The regulatory interventions did not show either an initial or sustained effect on fatal or non-fatal injuries, with effect sizes of 0.79 (95% CI 0.00 to 1.58) and 0.23 (95% CI 0.03 to 0.43). The safety campaign intervention resulted in a decrease in injuries at the company level but an increase at the regional level. Training interventions, inspections or the introduction of occupational health services did not result in a significant reduction of non-fatal injuries in single studies. A multifaceted drug-free workplace programme at the company level reduced non-fatal injuries in the year following implementation by -7.6 per 100 person-years (95% CI -11.2 to -4.0) and in the years thereafter by -2.0 per 100 person-years per year (95% CI -3.5 to -0.5).