Intervention: MANDATORY OHSMS
Bill 70 is a piece of legislation titled Occupational Health and Safety Act which took effect in October 1979. This legislation required organizations to take on an Internal Responsibility System. This system places greater emphasis on having employers and employees regulate their own working conditions. One key element of the legislation is the requirement for workplaces to form a Joint Health and Safety Committee (JHSC). The legislation applies to workplaces with over 20 employees and exempts some non-manufacturing firms.
Data Collection, Data Transformation, and Measurement Properties:
6 Final OHS Outcomes
Frequency of lost-time accidents: The authors note that the number of lost-time accidents is a good outcome because it is more likely to be reported than non-lost time accidents. However, lost-time accidents may be affected by socioeconomic circumstances of the injured person. For example, an injured worker may not take off the necessary time for recovery if he or she cannot afford such a loss in income.
Multiple regression, t-test for the beta coefficients: Regression analyses for the firms in the manufacturing and retail sectors are presented separately and then compared. There are two types of regression analyses conducted for each sector: (1) compare the beta coefficient for the Bill 70 variable in the manufacturing sector regression analysis TO the beta coefficient for the Bill 70 variable in the retail sector regression analysis (just two periods 76-79 VS 80- 89). (2) compare the beta coefficients for three period variables (1980, 1981, & 1982+) in manufacturing sector regression analysis TO the beta coefficients for three periods in the retail sector regression analysis. The purpose of the second regression is to see if there are delayed effects of Bill 70. In both regression models, dummy variables for time trend, industry rate group, and union status were included. An analysis that included a quadratic trend for time was also conducted. The analyses were based on 5,400 workplace-year observations for the manufacturing firms and 2,494 for the retail firms.
Intermediate OHS Outcomes Final OHS Outcomes
Effect estimates: (1st Regression – beta coefficient for Bill 70) Manufacturing = -0.015, Retail = -0.004; (2nd Regression – beta coefficients for 1980, 1981 and 1982+) Manufacturing = -0.011, -0.014, -0.024, Retail = -0.005, -0.3, -0.5
P-value: No p-values are stated. Only whether the coefficient was significant or not was reported. But because n is greater than 30, z scores apply. Therefore, (1st Regression – p value for Bill 70) Manufacturing less than 0.01, Retail greater than 0.05; (2nd Regression
p value for 1980, 1981 and 1982+) Manufacturing = less than 0.01,
less than 0.01, less than 0.01, Retail = greater than 0.05, greater than 0.05, greater than 0.05
Institute for Work & Health