Impact of a workplace peer-focused substance abuse prevention and early intervention program.
PeerCare is a workplace peer intervention program that focuses on changing workplace attitudes toward on-the-job substance use and trains workers to recognize, intervene with, and refer coworkers who have a problem.
                Monthly injuries at the study company (January 1983 through June 1996) were compared to counts at four other companies in the same industry. Using these panel data, fixed-effects negative binomial regression measured the association of the percentage of the workforce covered by PeerCare with the workplace injury rate.
                For every 1% increase in the workforce covered with PeerCare, the risk of injury declined by 0.9984 (95% confidence interval, 0.9975-0.9994). These findings suggest that, by June 1996, when 86% of the workforce was covered under PeerCare, the program had reduced injury rates by an average 14% per month.
                The findings support the implementation of peer intervention programs as a means to reduce workplace injuries.
There is insufficient evidence to advise for or against the use of drug and alcohol testing of occupational drivers for preventing injuries as a sole, effective, long-term solution in the context of workplace culture, peer interaction and other local factors. Cluster-randomised trials are needed to better address the effects of interventions for injury prevention in this occupational setting.