A case study of stress and mass psychogenic illness in industrial workers.

Outbreaks of fainting, nausea, and weakness among several hundred workers led to an investigation of industrial conditions. Repeated and extensive monitoring failed to detect levels of any substance that might explain these reactions. In a subsequent investigation of the psychosocial environment, the authors used a combination of observations, inventories, and interviews to determine whether psychosocial factors might explain this phenomenon. A multiple regression analysis identified (in order of importance) work intensity, mental strain, work/home problems, education, and sex as independent predictors explaining 33% of the overall severity of illness. The work was high-pressured, repetitive, monotonous, and noisy. This profile is consistent with reports of mass psychogenic illness and with research indicating that such work can be distressing and unhealthy.