OBJECTIVE:The objective of this study was to identify clinical and social predictors of application for Social Security Disability Insurance (SSDI) in workers' compensation claimants with low back pain. METHODS:Archival and interview data were analyzed for 1372 Missouri claimants who were, on average, nearly 42 months postinjury. RESULTS:Two hundred sixty-five (19.3%) claimants were receiving SSDI (8.0%) or had applied for SSDI (11.3%). Logistic regression indicated that black race, older age, herniated disc diagnosis, surgery, and longer time since injury were associated with increased odds of SSDI. Higher preinjury wage, more education, and higher satisfaction with medical treatment and/or treatment by employer were associated with decreased odds of SSDI. CONCLUSIONS:Application for SSDI among claimants with occupational low back pain is associated with social factors like race, satisfaction, and socioeconomics as well as clinical factors like diagnosis and surgery.