According to researchers, the study's findings were counterintuitive: Claimants with higher disability ratings – which suggest higher severity and less ability to work – fared better than those with lower ratings.
"A disability rating is supposed to reflect the amount of impairment a person has at the time that a case is closed," said Raymond Tait, Ph.D., a professor of psychiatry at St. Louis University School of Medicine and the principal investigator and lead author of the study article. "The presumption is that levels of impairment are stable and related to day-to-day levels of function. I was shocked that the associations between disability rating and subsequent levels of function weren't stronger.
"While surgery inflated disability ratings, there appeared no relationship between surgery outcomes and how a person did thereafter."
The study, which is detailed in an article in the December issue of the Journal of Pain, is the product of the work of researchers from St. Louis University, the University of Florida and the University of North Carolina at Chapel Hill.
According to Dr. Nortin Hadler, a professor of medicine and microbiology at the University of North Carolina at Chapel Hill's School of Medicine and co-author of the study, "administrative decisions made at the end of the workers' compensation claim process about the ability of someone to work after back injury has very little predictive validity."
"Clearly, the rating schemes for workers' compensation are inconsistent, and that fact is stirring enormous pots across the country," Hadler said. "If the outcomes from Missouri generalize, then there is a need to reform how disability is determined."
Despite Disparity in Care, Whites Fare No Better than Blacks
In "another paradoxical finding," according to the researchers, the study showed that white claimants fared no better than blacks – even though previous studies found that blacks were much less likely than whites to be diagnosed with a herniated disk or to have back surgery, had less money spent on their care and received lower disability ratings and smaller settlements.
"It's one of the more perverse observations in our study," Hadler said. "African-Americans were much less likely to be operated on, but the care that the whites got, even though it looks like more care – because it's surgery and it's more expensive – didn't do anything for them."
For the study, Tait and colleague John Chibnall, Ph.D., also a professor of psychiatry at St. Louis University, analyzed about 1,500 Missouri workers – 580 African-Americans and 892 Caucasians – whose workers' compensation claims for lower back pain were settled between Jan. 1, 2001, and June 1, 2002.
The researchers interviewed the employees 21 months after their settlements to find out how they were doing. They asked questions about pain intensity, general physical and mental health and whether they currently were working.
Tait and Chibnall said that their findings "raise questions about both the validity and the fairness of the current disability determination program."
"Disability settlements are designed to give people money toward a fresh start," they said. "Those settlements do not appear to reflect the residual levels of disability that people actually experience."