[A two-year program to promote participatory workplace environmental improvements at small enterprises with fewer than ten employees].

Objective: This study aimed to determine the influence of participatory workplace environmental improvement program on reducing job stress and workers' psychological distress at small enterprises (i.e., less than 10 employees). Furthermore, this study aimed to clarify important factors for success of this program as well.

Methods: The model program was tested in a small enterprise with eight employees between October 2014 and January 2017. Moreover, five employees participated in the annual work environment improvement workshops for two consecutive years. During both years, the New Brief Job Stress Questionnaire (80-item version) was used to measure work-related stress before (baseline) and after (post-three months and post-12 months) the workshops. To assess the extent of an intervention effect, the questionnaire data were analyzed using the Friedman test and the multiple comparison test annually. In addition, continuous data were analyzed during the two years. The statistical significance of the differences across time was determined at the p < .10 cutoff value because the number of participants was small. The effect size was also calculated. The participants were interviewed regularly.

Results: For both years, the employees implemented action plans within one month of completing the workshops. In the first year, the data for the Friedman test indicated a significant change in role conflict, job resources (workgroup-level), respect for individuals, fair personnel evaluations, work-self balance (positive), workplace social capital, and job satisfaction. In the multiple comparison test, significant changes manifested in role conflict and workplace social capital. In the second year, significant changes were found regarding role conflict and fair personnel evaluations for the Friedman test, demonstrating significant changes in role conflict in the multiple comparison test. As per the two-year survey results, the Friedman test indicated significant changes in role conflict, respect for individuals, and fair personnel evaluations, while the multiple comparison test demonstrated no significant changes. Over time, favorable changes were found regarding role conflict in the first year; however, undesirable changes were found regarding the other statistically significant items. The interviews revealed both positive and negative opinions.

Conclusions: This study found the effects of the participatory workplace environment improvement program to be limited. Thus, the program should be improved to reduce its adverse effects as well as the participants' negative opinions.