This longitudinal, quasi-experiment tested whether or not a work reorganization intervention can improve stress-related outcomes by increasing people's job control. To this end, the authors used a participative action research (PAR) intervention that had the goal of reorganizing work, so as to increase the extent to which people had discretion and choice in their work. Results indicated that the PAR intervention significantly improved people's mental health, sickness absence rates, and self-rated performance at a 1-year follow-up. Consistent with occupational health psychology theories, increase in job control served as the mechanism, or mediator, by which these improvements occurred. Discussion focuses on the need to understand the mechanisms by which work reorganization interventions affect change.
Job control 3Job control mediates change in a work reorganization intervention for stress reduction For years, occupational health psychologists have advocated modifying aspects of the work environment that are associated with mental ill-health (e.g., Bunce & West, 1996;Ivancevich, Matteson, Freedman, & Phillips, 1990;Newman & Beehr, 1979;Murphy, 1984;Quick, Quick, Nelson, & Hurrell, 1997). These environmental risk factors arise from (unhelpful) ways in which work is organized. Work organization refers to the scheduling of work, job structure and design, interpersonal aspects of work, and management style (National Institute of Occupational Safety and Health [NIOSH], 1996). In the context of occupational health psychology, work reorganization denotes interventions that change work organization variables, in an effort to alleviate stress-related outcomes, such as mental ill-health, job dissatisfaction, sickness absence, and poor work performance. Largely, the wide-ranging call for the use of work reorganization to improve these outcomes has gone unanswered or the responses have been incomplete (e.g., NIOSH, 1996). In particular, there is a lack of methodologically sound, empirical research that has investigated this strategy for reducing and preventing mental illhealth. Furthermore, the mechanisms by which these interventions improve stress-related outcomes have not been investigated, using commonly recommended, rigorous, procedures (see Barnett, Gareis, & Brennan, 1999;Baron & Kenny, 1986;Kenny, 1998).Occupational health psychology theories posit a number of work characteristics by which work reorganization interventions may improve stress-related outcomes (see Parker & Wall, 1998). The one that is identified most ubiquitously appears to be job control, or the extent to which people have discretion and choice in their work. The primary goal of the 12-month, longitudinal, quasi-experiment described here was to determine in a rigorous manner whether a work reorganization intervention can actually improve stress-related outcomes by increasing Job control 4 people's job control. We sought to do this within the context of our second objective, which was to examine the effectiveness of this type of intervention...