Study Design. Systematic review.
Objective. To identify, describe, and evaluate common outcome measures in patients with chronic low back pain (CLBP).
Summary of Background Data. The treatment of CLBP has been associated with multiple clinical challenges. Further complicating this is the myriad of outcome scores used to assess treatment of CLBP. These scores have been used to examine different domains of patient satisfaction and quality of life in the literature. Critical assessment of the frequency, parity, and the quality of these outcomes are essential to improve our understanding of CLBP.
Methods. A systematic review of the English-language literature was undertaken for articles published from January 2001 through December 31, 2010. Electronic databases and reference lists of key articles were searched to identify measures used to evaluate outcomes in six different domains in patients with CLBP. The titles and abstracts of the peer-reviewed literature of LBP were searched to determine which of these measures were most commonly reported in the literature and which have been validated in populations with CLBP.
Results. We identified 75 outcome measures cited to evaluate CLBP. Twenty-nine of these outcome measures were excluded because of only a single citation leaving 46 measures for the evaluation. The most commonly used functional outcomes were the Oswestry Disability Index, Roland Morris Disability Index, and range of motion. For pain, the Numeric Pain Rating Scale, Brief Pain Inventory, Pain Disability Index, McGill Pain Questionnaire, and visual analog scale were most commonly cited. For psychosocial function, the Fear Avoidance Beliefs Questionnaire, Tampa Scale for Kinesiophobia, and Beck Depression Inventory were most commonly used. For generic quality of life, short form 36, Nottingham Health Profile, short form 12, and Sickness Impact Profile were the most common measures. For objective measures, the work status/return to work, complications or adverse events, and medications used were the most commonly cited. For preference-based measures, the Euro-Quol 5 dimensions and short form 6 dimensions were most commonly cited. The validity, reliability, responsiveness, universality, and potential proprietary requirements are summarized for each.
Conclusion. Outcome measures should be routinely assessed in patients with CLBP. The choice of appropriate outcome measure should be influenced by the study objectives and design, as well as properties of the particular measure within the context of CLBP.
Clinical Recommendations. Recommendation 1: When selecting the appropriate outcome measures for clinical or research purposes, consider domains that best measure what are most important to patients. Measures that are valid, reliable, and responsive to change should be considered first. Other considerations include the number of items required (especially in the context of multiple measures), whether the measure is validated in the relevant language, and the associated costs or fees. Strength: Strong
Recommendation 2: Domains of greatest importance include pain, function, and quality of life. If cost utilization is a priority, then preference-based measures should be considered. For pain, we recommend the VAS and NRPS because of their ease of administration and responsiveness. For function, we recommend the ODI and RMDQ. The SF-36 and its shorter versions are most commonly used and should be considered if quality of life is important. If cost utility is important, consider the EQ-5D or SF-6D. Psychosocial tests are best used as screening tools prior to surgery because of their lack of responsiveness. Complications should always be assessed as a standard of clinical practice. Return to work and medication use are complicated outcome measures and not recommended unless the specific study question is focused on these domains. Consider staff and patient burden when prioritizing one's battery of measures.
Multiple outcome measures have been utilized in the assessment of chronic low back pain. The outcome measures lack parity not only in the domains examined but also the quality of their assessment. This study critically assesses these outcome measures for chronic low back pain in regard to range, frequency of use, and quality.
*Department of Orthopaedic Surgery, Harborview Medical Center, Seattle, WA;
†Spectrum Research, Inc., Tacoma, WA;
‡Departments of Spine Surgery and Orthopedic Residency, Eisenhower Army Medical Center, Ft Gordon, GA;
§Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, Tennessee;
¶Department of Orthopaedic Surgery, University of Washington Medical Center, Seattle, WA.
Address correspondence and reprint requests to Michael J Lee, MD, Department of Orthopaedic Surgery, University of Washington Medical Center, Box 356500, 1959 Pacific Ave NE, Seattle, WA 98195; E-mail: firstname.lastname@example.org.
Acknowledgment date: May 6, 2011. First Revision date: June 14, 2011. Second Revision date: July 18, 2011. Acceptance date: June 21, 2011.
The manuscript submitted does not contain information about medical device(s)/drug(s).
Professional Organization and Foundation funds were received to support 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.
Analytic support for this work was provided by Spectrum Research, Inc., with funding from the AOSpine North America.