Voluntary OHSMSs All studies involving voluntary OHSMS
interventions reported positive findings. While the outcomes measured varied among studies, the findings included increased implementation over time, better safety climates, increased hazard reporting by employees, more organizational action taken on occupational and health issues and decreased workers’ compensation premiums. It is likely that the size of the observed declines in premium rates (23 and 52 percent) would be considered important by stakeholders.
However, all the studies in this group were of only “moderate” quality, largely because their study designs were so simple. This meant that reviewers had some doubts regarding the validity of the study findings. Three of the four studies involved single workplaces, making the applicability of the findings to other workplace settings uncertain. There was, moreover, reason to suspect that publication bias might account for the consistency of positive results in these studies.
1.4.2 Mandatory OHSMSs Of the five studies examining mandatory OHSMSs, three involved Norwegian worksites and two evaluated the impact of Canadian provincial regulations introduced in the 1970s. All five studies reported positive findings. Some documented increased OHSMS implementation over time. Others found that OHSMS implementation improved employee perceptions of the physical and of the psychosocial working environment and increased workers’ participation in health and safety activities. Implementation also reduced rates of lost time injury in workplaces and led to increases in productivity. It is likely that the size of the observed changes in OHSMS implementation and injury rate would be considered important by stakeholders.
All the studies in this group had moderate methodological limitations. These arose again from the simplicity of the study designs, especially the cross-sectional studies where the direction of causality was not clear.
No studies were found that compared voluntary and mandatory OHSMS interventions directly. No studies of sufficient quality were found that examined facilitators of and barriers to OHSMS implementation or effectiveness, nor were any found that estimated the cost of OHSMS implementation.
Effectiveness of Occupational Health & Safety Management Systems: A Systematic Review