Adjusting rehabilitation costs and benefits for health capital: The case of low back occupational injuries

Introduction Case-mix adjustments for treatment/rehabilitation costs and benefits of non-traumatic injuries, such as occupational back pain, are much more difficult than adjustments for traumatic injuries. We present a new method for adjusting for severity differences in the costs and benefits of treating occupational low back injuries. Methods Using initial post-injury differences in the health capital of prospective sample of 1,831 occupational related back pain patients, we combine survey data with workers' compensation claim files and medical billing information to adjust the costs and benefits of treatment using multivariate techniques. Results We find that large differences in the net benefits of treatment between the three lowest cost provider groups virtually disappear once adjustments are made for worker's health capital (injury severity) at entry into treatment. Conclusions Once adjustments are made for initial health capital immediately after injury, the net benefits of treating occupational low back pain are virtually identical for physician only care, physician plus physical therapy care, and chiropractic care. Net benefits of care are lower for combined physician/chiropractic care, and lowest for all other forms of care (principally, treatment by orthopedic surgeons). Our method is readily adapted for comparisons among individual health care/occupational rehabilitation professionals or among group practices and other health care organizations.