Centralization: Prevalence and Effect on Treatment Outcomes Using a Standard Operational Definition and Measurement Method

Mark W. Werneke, Linda Resnik, Paul W. Stratford, Adrian Reyes, Dennis L. Hart
STUDY DESIGN: Retrospective, observational cohort design. OBJECTIVES: Purpose 1 was to determine the association between age, symptom chronicity, and prevalence of centralization in a sample of patients with nonserious cervical or lumbar spinal syndromes referred to a hospital-based outpatient rehabilitation clinic. Purpose 2 was to examine if classifying these patients at intake by centralization or noncentralization predicts functional status, pain intensity, and number of treatment visits at discharge from rehabilitation. Purpose 3 was to compare clinically meaningful changes in functional status and pain intensity between patients subgrouped by centralization and noncentralization. BACKGROUND: Variations in operational definitions and measurements used to identify centralization affect patient classification, contribute to variation in reported prevalence rates, and influence treatment strategy and outcome interpretation. Investigating a standardized operational definition and measurement method for centralization may reduce practice and outcomes variation. METHODS AND MEASURES: Adults (n = 418) with cervical or low back syndromes (mean ± SD age, 58 ± 17; range 19–91; 33% male; 76% lumbar symptoms; 53% chronic symptoms) were assessed. Therapists classified patients using a standardized operational definition and method for centralization during initial evaluation. Prevalence rates were calculated for centralization by age and acuity. Multivariate models were used to assess discharge functional status, pain intensity, and visits while controlling important variables. Percentage of patients subgrouped by centralization and noncentralization achieving minimal clinically important differences (MCID) in functional status and pain intensity was assessed. RESULTS: Overall prevalence rate for centralization was 17%, but increased for patients who were younger and reported acute symptoms regardless of body part. For patients with lumbar syndromes, noncentralization was associated with lower discharge functional status and more pain, but not associated with visits compared to patients classified as centralization. For patients with cervical syndromes, noncentralization was associated with more pain but not associated with functional status or number of visits compared to patients classified as centralization. Pain pattern classification affected percentage of patients with lumbar and cervical impairment achieving MCID. CONCLUSION: Results supported the clinical use of a standardized definition of centralization to facilitate patient classification and management and interpretation of outcomes. LEVEL OF EVIDENCE: Prognosis, level 2b.

J Orthop Sports Phys Ther. 2008;38(3):116-125, published online 9 November 2007. doi:10.2519/jospt.2008.2596

KEY WORDS: cervical spine, lumbar spine, neck, patient classification

Guide to Outcomes Measurement for Patients With Low Back Pain Syndromes

Linda Resnik, Edward A. Dobrzykowski

The Guide for Physical Therapist Practice states that the physical therapist determines the expected outcomes for each intervention and engages in outcomes data collection and analysis. Outcomes tracking provides a systematic way for therapists to monitor treatment effectiveness and efficiency. A familiarity with outcome measures for the patient with low back pain is indispensable for therapists in the outpatient orthopaedic setting, where patients with lumbar pain often comprise the majority of the caseload. The therapist must be able to evaluate and choose appropriate measurement tools and understand the clinical meaning of measurements to employ these instruments successfully. The purpose of this article is to review measurement instruments for patients with low back pain and to offer practical guidelines for selection and use of outcome measures for this population. The reliability, validity, sensitivity to change, and utility of common outcome measures are discussed. An overview of generic, disease-specific, and patient-specific tools is provided with specific commentary on the use of the SF-36, SF-12, Oswestry Questionnaire, Roland-Morris Questionnaire, and patient-specific tools. Practical guidelines for utilizing outcome measures in clinical practice and the overall benefits of outcomes tracking are highlighted.

J Orthop Sports Phys Ther. 2003;33(6):307-318.

Key Words: low back pain, outcomes data collection, analysis

Journal of Orthopaedic & Sports Physical Therapy - Linda Resnik, PT, PhD, OCS

Centralization: Prevalence and Effect on Treatment Outcomes Using a Standard Operational Definition and Measurement Method

Guide to Outcomes Measurement for Patients With Low Back Pain Syndromes