Teaching and social support: effects on knowledge, attitudes, and behaviors to prevent low back injuries in industry

An educational program designed to reduce low back injuries was modeled after several well-known back schools and taught to postal workers in a randomized trial of about 4,000 workers. Physical therapists taught 3 hours of class sessions, including knowledge, skills, and individual work station assessment, to small groups of workers and supervisors, with reinforcement every 6 months afterward. At 2 1/2 years, a random sample of 209 workers was surveyed for program impact on intermediate outcomes. We observed increased knowledge among experimental unit workers, but no significant improvements in behaviors associated with back health or in proportion of workers with tired backs. Experimental unit workers who had received training by the time of the survey were less likely to report helping/reinforcement for healthy behaviors than controls or untrained experimental unit workers. The program might have led trained workers to perceive a lack of support and reinforcement for back safety among coworkers and supervisors by sensitizing them to what is possible and raising expectations. There appeared to be group social effects in the dissemination of knowledge and perhaps of helpful behaviors; however, it is apparent that worker social support for change in health behaviors is a complex phenomenon that cannot always be relied upon to enhance program goals.