Abstract
Objective
To evaluate if allocation concealment and intention-to-treat (ITT) analysis influence
the treatment effects of physical therapy interventions in low back pain (LBP) trials.
Data Sources
We searched on PubMed, Embase, Cochrane Database of Systematic Reviews, Physiotherapy
Evidence Database (PEDro), and CINAHL up to February 2017.
Study Selection
We included LBP trials that compared physical therapy interventions to placebo or
no intervention or minimal intervention with pain or disability outcomes.
Data Extraction
Information about allocation concealment and ITT analysis was extracted from PEDro
and pain and disability outcomes converted to a 0-100 scale. A meta-regression was
performed to evaluate the influence of these methodological features of interest on
treatment effects. Other covariates included in the meta-regression were sample size
and sequence generation.
Data Synthesis
We identified 128 eligible trials (pooled N=20,555 participants). A total of 44.5%
of the trials achieved allocation concealment, while 32% performed ITT analysis. Meta
regression analyses showed no influence of allocation concealment on treatment effects
for pain (regression coefficient 0.009; 95% confidence interval [CI] -2.91 to 2.91)
and disability (regression coefficient 1.13; 95% CI -1.35 to 3.62), and no influence
of ITT analysis for pain (regression coefficient 1.38; 95% CI -1.73 to 4.50) or disability
(regression coefficient 1.27; 95% CI -1.39 to 3.64). For the other covariates, there
was also no clinically significant influence on the treatment effects.
Conclusion
There is no influence of allocation concealment or ITT analysis on treatment effects
of physical therapy interventions for pain and disability in LBP trials.
Keywords
List of abbreviations:
CI (confidence interval), ITT (intention-to-treat), LBP (low back pain), PEDro (Physiotherapy Evidence Database), RCT (randomized controlled trial)To read this article in full you will need to make a payment
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Article info
Publication history
Published online: January 30, 2019
Footnotes
Disclosures: none.
Supported by São Paulo Research Foundation (FAPESP) (grant no. 2016/10317-0).
Clinical Trial Registration No.: CRD42016052347.
Identification
Copyright
© 2019 by the American Congress of Rehabilitation Medicine
