Estimating Contextual Effect in Nonpharmacological Therapies for Pain in Knee Osteoarthritis: A Systematic Analytic Review.


Author: Chen AT1, Shrestha S2, Collins JE3, Sullivan JK4, Losina E5, Katz JN6

Affiliation: <sup>1</sup>Orthopaedic and Arthritis Center for Outcomes Research (OrACORe) and Policy and Innovation eValuation in Orthopaedic Treatments (PIVOT) Center, Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, Massachusetts, United States of America. Electronic address: atchen@bwh.harvard.edu.

<sup>2</sup>Orthopaedic and Arthritis Center for Outcomes Research (OrACORe) and Policy and Innovation eValuation in Orthopaedic Treatments (PIVOT) Center, Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, Massachusetts, United States of America. Electronic address: sshrestha7@partners.org.

<sup>3</sup>Orthopaedic and Arthritis Center for Outcomes Research (OrACORe) and Policy and Innovation eValuation in Orthopaedic Treatments (PIVOT) Center, Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, Massachusetts, United States of America; Harvard Medical School, Boston, Massachusetts, United States of America. Electronic address: jcollins13@bwh.harvard.edu.

<sup>4</sup>Orthopaedic and Arthritis Center for Outcomes Research (OrACORe) and Policy and Innovation eValuation in Orthopaedic Treatments (PIVOT) Center, Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, Massachusetts, United States of America. Electronic address: jsullivan76@bwh.harvard.edu.

<sup>5</sup>Orthopaedic and Arthritis Center for Outcomes Research (OrACORe) and Policy and Innovation eValuation in Orthopaedic Treatments (PIVOT) Center, Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, Massachusetts, United States of America; Harvard Medical School, Boston, Massachusetts, United States of America; Section of Clinical Sciences, Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts, United States of America; Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts, United States of America. Electronic address: elosina@bwh.harvard.edu.

<sup>6</sup>Orthopaedic and Arthritis Center for Outcomes Research (OrACORe) and Policy and Innovation eValuation in Orthopaedic Treatments (PIVOT) Center, Department of Orthopaedic Surgery, Brigham and Women's Hospital, Boston, Massachusetts, United States of America; Harvard Medical School, Boston, Massachusetts, United States of America; Section of Clinical Sciences, Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, Massachusetts, United States of America; Departments of Epidemiology and Environmental Health, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America. Electronic address: jnkatz@bwh.harvard.edu.
Conference/Journal: Osteoarthritis Cartilage.
Date published: 2020 May 13
Other:
  Pages: S1063-4584(20)31019-0   ,  Special Notes: doi: 10.1016/j.joca.2020.05.007. [Epub ahead of print]   ,  Word Count: 256  
    OBJECTIVE: Conduct a systematic review and use meta-analytic techniques to estimate the proportion of total treatment effect that can be attributable to contextual effects (PCE) in adults receiving nonpharmacological, nonsurgical (NPNS) treatments for knee osteoarthritis (OA).



DESIGN: We reviewed the published literature to identify five frequently studied NPNS treatments for knee OA: exercise, acupuncture, ultrasound, laser, and transcutaneous electrical nerve stimulation (TENS). We searched for randomized controlled trials (RCTs) of these treatments and abstracted pre- and post-intervention pain scores for groups receiving placebo and active treatments. For each study we calculated the PCE by dividing the change in pain in the placebo group by the change in pain in the active treatment group. We log transformed the PCE measure and pooled across studies using a random effects model.



RESULTS: We identified 25 studies for analysis and clustered the RCTs into two groups: acupuncture and topical energy modalities (TEM). 13 acupuncture studies included 1,653 subjects and 12 TEM studies included 572 subjects. The combined PCE was 0.61 (95% CI 0.46 - 0.80) for acupuncture and 0.69 (95% CI 0.54 - 0.88) for TEM.



CONCLUSION: Our findings suggest that about 61% and 69% of the total treatment effect experienced by subjects receiving acupuncture and TEM treatments, respectively, for knee OA pain may be explained by contextual effects. Contextual effects may include the placebo effect, changes attributable to natural history, and effects of co-therapies. These data highlight the important role of contextual effects in the response to NPNS OA treatments.



Copyright © 2020 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.



KEYWORDS: contextual effect; knee osteoarthritis; pain; placebo effect



PMID: 32416220  DOI: 10.1016/j.joca.2020.05.007