Do worker's compensation patients with neck pain have lower SF-36 scores?

Poorer outcomes of treatment are reported in patients with spinal disorders who receive worker's compensation. The reason for their suboptimal outcomes is unclear. No study has examined the relationship between worker's compensation and SF-36 health status of patients with neck pain. The aim of our study was to compare the self-perceived health status of patients with neck pain receiving worker's compensation, with that of patients not receiving worker's compensation. A cross-sectional study was conducted on 2356 patients with neck pain who were evaluated at the 27 centers comprising the National Spine Network, between January 1998 and April 2000. The outcome measures used were the eight individual and two component scores of the SF-36 health survey. Of the 2356 patients, 171 (7%) were receiving worker's compensation. Bivariate analyses revealed seven individual scores (except General Health) and two summary scores of the SF-36 were significantly lower in patients receiving worker's compensation. After controlling for confounding covariates, worker's compensation status was a significant predictor of lower SF-36 scores for Physical Functioning ( P<0.05). The results of this study indicate that worker's compensation status is associated with poorer Physical Functioning in patients presenting with neck pain. Another significant finding of the study is that confounding factors can exert major effects on the SF-36 scores obtained on normal validated instruments.