Exercise treatment effect modifiers in persistent low back pain: An individual participant data meta-analysis of 3514 participants from 27 randomised controlled trials

Jill A. Hayden, Maria N. Wilson, Samuel Stewart, Jennifer L. Cartwright, Andrea O. Smith, Richard D. Riley, Maurits Van Tulder, Tom Bendix, Francesca Cecchi, Leonardo O.P. Costa, Ninna Dufour, Manuela L. Ferreira, Nadine E. Foster, Maruti R. Gudavalli, Jan Hartvigsen, Pieter Helmhout, Jan Kool, George A. Koumantakis, Francisco M. Kovacs, Tiina KuukkanenAudrey Long, Luciana G. Macedo, Luciana A.C. Machado, Chris G. Maher, Wolf Mehling, Giovanni Morone, Tom Peterson, Eva Rasmussen-Barr, Cormac G. Ryan, Tuulikki Sjögren, Rob Smeets, J. Bart Staal, Monica Unsgaard-Tøndel, Henry Wajswelner, Ella W. Yeung, on behalf of Chronic Low Back Pain IPD Meta-Analysis Group

Research output: Contribution to journalReview articlepeer-review


Background: Low back pain is one of the leading causes of disability worldwide. Exercise therapy is widely recommended to treat persistent non-specific low back pain. While evidence suggests exercise is, on average, moderately effective, there remains uncertainty about which individuals might benefit the most from exercise. Methods: In parallel with a Cochrane review update, we requested individual participant data (IPD) from high-quality randomised clinical trials of adults with our two primary outcomes of interest, pain and functional limitations, and calculated global recovery. We compiled a master data set including baseline participant characteristics, exercise and comparison characteristics, and outcomes at short-term, moderate-term and long-term follow-up. We conducted descriptive analyses and one-stage IPD meta-analysis using multilevel mixed-effects regression of the overall treatment effect and prespecified potential treatment effect modifiers. Results: We received IPD for 27 trials (3514 participants). For studies included in this analysis, compared with no treatment/usual care, exercise therapy on average reduced pain (mean effect/100 (95% CI) -10.7 (-14.1 to -7.4)), a result compatible with a clinically important 20% smallest worthwhile effect. Exercise therapy reduced functional limitations with a clinically important 23% improvement (mean effect/100 (95% CI) -10.2 (-13.2 to -7.3)) at short-term follow-up. Not having heavy physical demands at work and medication use for low back pain were potential treatment effect modifiers - these were associated with superior exercise outcomes relative to non-exercise comparisons. Lower body mass index was also associated with better outcomes in exercise compared with no treatment/usual care. This study was limited by inconsistent availability and measurement of participant characteristics. Conclusions: This study provides potentially useful information to help treat patients and design future studies of exercise interventions that are better matched to specific subgroups. Protocol publication: https://doi.org/10.1186/2046-4053-1-64.

Original languageEnglish
JournalBritish Journal of Sports Medicine
Publication statusE-pub ahead of print - Nov 1 2019


  • exercise rehabilitation
  • intervention effectiveness
  • lower back
  • meta-analysis

ASJC Scopus subject areas

  • Orthopedics and Sports Medicine
  • Physical Therapy, Sports Therapy and Rehabilitation


Dive into the research topics of 'Exercise treatment effect modifiers in persistent low back pain: An individual participant data meta-analysis of 3514 participants from 27 randomised controlled trials'. Together they form a unique fingerprint.

Cite this