Cross-sectional investigation and follow-up of patients with low back pain.
To evaluate the capacity of the INTERMED-a biopsychosocial assessment and classification system for case complexity-to identify patients with a chronic, disabling course of low back pain and to predict treatment outcome.
An impressive number of biologic and nonbiologic factors influencing the course of low back pain have been identified. However, the lack of a concise, comprehensive, reliable and validated classification system of this heterogeneous patient population hampers preventive and therapeutic progress.
The INTERMED was used to assess patients with low back pain, who participated in a functional rehabilitation program (n = 50) and patients with low back pain who applied for disability compensation (n = 50). Patients of the rehabilitation program were observed to assess the effects of treatments.
The INTERMED distinguished between patients in different phases of disability and provided meaningful information about the biopsychosocial aspects of low back pain. In hierarchical cluster analysis two distinct clusters emerged that differed in the degree of case complexity and treatment outcomes.
This first application of the INTERMED indicates its potential utility as a classification system for patients with low back pain.
From the *Psychiatric Liaison Service, Department of †Orthopedics, ‡Center of Disability Evaluation, §Service of Rheumatology, and ∥Psychiatric Outpatient Clinic, University Hospital, Lausanne, Switzerland; ¶CL-Psychiatry Service, Free University Hospital, Amsterdam; and #Department of Geriatric Medicine, University Hospital, Groningen, The Netherlands; and **Department of Psychiatry, North Western Memorial Hospital, Chicago, Illinois.
Supported by the Swiss National Foundation Grant 3232-42162 and by European Union BIOMED 1 Grant BMH1-CT93-1180.
Acknowledgment date: January 9, 1998.
First revision date: March 27, 1998.
Acceptance date: June 1, 1998.
Device status category: 1.
Address reprint requests to: Friedrich C. Stiefel, MD; Service of Consultation-Liaison Psychiatry; University Hospital; CH-1011 Lausanne; Switzerland.