Study Design. Prospective observational study of prognostic indicators, using data from a randomized, controlled trial of physiotherapy care of acute low back pain (ALBP) with follow-up at 6 weeks, 3 months, and 6 months.
Objective. To evaluate which patient profile offers the most useful guide to long-term outcome in ALBP.
Summary of Background Data. The evidence used to inform prognostic decision-making is derived largely from studies where baseline data are used to predict future status. Clinicians often see patients on multiple occasions so may profile patients in a variety of ways. It is worth considering if better prognostic decisions can be made from alternative profiles.
Methods. Clinical, psychological, and demographic data were collected from a sample of 54 ALBP patients. Three clinical profiles were developed from information collected at baseline, information collected at 6 weeks, and the change in status between these 2 time points. A series of regression models were used to determine the independent and relative contributions of these profiles to the prediction of chronic pain and disability.
Results. The baseline profile predicted long-term pain only. The 6-week profile predicted both long-term pain and disability. The change profile only predicted long-term disability (P < 0.01). When predicting long-term pain, after the baseline profile had been added to the model, the 6-week profile did not add significantly when forced in at the second step (P > 0.05). A similar result was obtained when the order of entry was reversed. When predicting long-term disability, after the 6-week profile was entered at the first step, the change profile was not significant when forced in at the second step. However, when the change profile was entered at the first step and the 6-week clinical profile was forced in at the second step, a significant contribution of the 6-week profile was found.
Conclusion. The profile derived from information collected at 6 weeks provided the best guide to long-term pain and disability. The baseline profile and change in status offered less predictive value.
Guidelines recommend multiple assessments of ALBP patients. We were interested in what information provides the best indicator of chronic status. The 6-week profile was the most useful predictor of long-term status. The baseline profile and change in status offered less predictive value.
From the *The University of Notre Dame Australia, School of Health Sciences, Western Australia, Australia; †Musculoskeletal Division, The George Institute for International Health, Sydney, Australia and Back Pain Research Group, University of Sydney, New South Wales, Australia; ‡Division of Population Health, Research Department of Primary Care and Population Health, Faculty of Biomedical Sciences, University College London Medical School, London, United Kingdom; and §Department of Health Sciences and Social Care, Brunel University, Middlesex, United Kingdom.
Acknowledgment date: August 4, 2008. First revision date: January 14, 2009. Second revision date: February 12, 2009. Acceptance date: February 16, 2009.
The manuscript submitted does not contain information about medical device(s)/drug(s).
Federal funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript.
Ethical approval was obtained from the Health Authorities Research Ethics Committee.
Address correspondence and reprint requests to B. M. Wand, PhD, The University of Notre Dame Australia, School of Health Sciences, 19 Mouat St Fremantle, WA 6959, Australia; E-mail: firstname.lastname@example.org