Occupational stressors, perceived injustice, and pathways to pain interference and insomnia among workers with headache or low back pain

The study examined the relationship between occupational stressors, perceived injustice, and health problems among 600 Japanese workers (300 with headache and 300 with low back pain). Researchers tested the Japanese version of the Injustice Experience Questionnaire-Short Form (IEQ-SF-J) and found it has a unidimensional structure with acceptable internal consistency (Cronbach's alpha = 0.82). Results showed that high job demands and low job control had indirect effects on pain interference, depressive symptoms, and insomnia through perceived injustice. IEQ-SF-J scores significantly correlated with pain, insomnia, and depressive symptoms. The study confirmed that perceived injustice plays an important role in linking occupational stress to health problems.