Treating chronic low back pain. I. Admissions to initial follow-up.

For a normative study of chronic low back pain (CLBP), 702 consecutive admissions to a large multidisciplinary CLBP treatment program were assessed at admission, discharge, and 1-month follow-up, using a variety of psychological and functional performance instruments. Both univariate and multivariate approaches to appraising success are evaluated. Psychological profiles demonstrated a substantial degree of disability at admissions, which is significantly reduced at follow-up. Both behavioral and cognitive aspects of performance, as evidenced by objective assessments of patients' physical abilities and verbalizations, improved as a direct function of length of stay in the treatment program and continued to show modest improvement through follow-up. Composite indices of improvement demonstrated favorable outcomes for no less than four in every ten, and as high as nine in every ten participants. Because of the large sample size, relationships both within and across measurement domains can be assessed statistically: the separate sets of outcome measures, with the exception of psychological profiles, are generally independent of each other.