One of the IC indices, termed “IC status”, was based on the manager’s stated assessment of the level of implementation at their garage (from “don’t know what an IC is” to “implemented IC”, on a five-point scale). The other, called the “IC index”, was based on 16 questions considered relevant to establishing IC in firms (e.g., “does the garage have a health a safety deputy?”). Variables from the garage workers’ questionnaires were scored on a 7-point scale (poor=1, good=7). The results of the multiple regression analyses showed that the IC index based on the 16 items was significantly correlated with 6 of the 9 intermediate OHS variables.17 These significant correlations all indicated that the IC had positive effects. Higher levels of correlation were obtained in the regression analysis with IC status as rated by managers (7 of the 9 were statistically significant). The highest correlations were with “satisfaction with HES activities at the garage” and the IC index (0.16, p<0.001) and the same variable with IC status as rated by the manager (0.15, p<0.001).
These findings from Torp et al. (2000) do provide some evidence of correlation between measures of IC implementation and some intermediate outcomes. The cross-sectional design is discussed by the authors as limiting the conclusions drawn from the study because of ambiguity in the direction of causality.18 Additionally, the respective response rates for the companies participating in the training and those not scheduled for training were not provided and differences may present the potential for selection bias towards better or poorer performers in HES. The exclusive use of self-reported measures suggests that reporting bias may be problematic.
4.4.3 Studies of final OHS outcomes Three of the studies of mandatory OHSMSs reported final OHS outcomes (Saksvik and Nytro, 1996; Torp et al., 2000; and Lewchuk et al., 1995).
In the previously described Norwegian study by Saksvik and Nytro (1996), the hypothesis was that the status of IC implementation was related to changes in the rates of absenteeism and accidents. Three levels of IC implementation were developed based on responses to 13 questions. The types of questions and IC implementation measures were as follows: one question (rated from “not started” to “finished” on a 5 point scale), “IC status after own opinion”; nine questions related to number of completed IC activities, “IC status quantitative measure”; and three questions based on the
17 The nine intermediate OHS variables were: satisfaction with HES activities at garage, satisfaction with physical working environment, satisfaction with psychosocial working environment, psychological job demands, decision authority, social support, HES-related management support, health-related support and control, and workers’ participation in HES activities.
18 The reviewers agreed and thought that factors such as “commitment to HES”, that could cause both better IC implementation and better HES outcomes, could result in a correlation between implementation and intermediate outcomes.
Effectiveness of Occupational Health & Safety Management Systems: A Systematic Review