RESUMEN

Small and medium-sized enterprise (SME) owners are at an increased risk of mental disorders in addition to stress directly related to their business performance. However, steps to protect SME owners' mental health are lacking, and no occupational stress scale has been developed to accurately understand the real-world situation. Based on a nationwide internet survey of 1,000 Japanese SME owners aged 20-79 years with five or more employees, we developed a novel occupational stress scale for SME owners. The 43-item scale assesses job stress factors and modifying factors (individual, non-work, and buffering factors). The validity and reliability of the scale were verified. The job stress factors were unique among SME owners and differed from those of employees, with moderate positive correlations with both psychological distress and presenteeism. Further, the study revealed the roles of modifying factors; work-family conflict increased presenteeism and psychological distress, while self-care and social support decreased them. The findings provide important insights for assessing psychological stress among SME owners, informing future mental health intervention strategies among this population.