Rheumatology studies make the evidence sound better than it is
One page on PainSci cites Mathieu 2012: Studying the Pain Studies
PainSci notes on Mathieu 2012:
Researchers determined that almost 25% of abstracts have misleading conclusions … and even more so if you look only at studies with negative results, where the rate of misleading conclusions jumps to an alarming 45%. That is, study abstracts clearly tend to make the evidence sound more positive than it is.
And of course that’s all that most people ever read. None of this is really surprising — if anything, I’m surprised it isn’t worse — but it is useful to have some hard data about it.
See also some entertaining commentary by Neil O’Connell for BodyInMind.org.
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
INTRODUCTION: Readers of scientific articles often read only the abstract and its conclusions because of lack of time or of access to the full-length articles.
OBJECTIVES: To assess the prevalence of misleading conclusions in abstracts of randomized controlled trials (RCTs) in rheumatology, determine whether trials are registered and whether abstract conclusions are based on the primary outcome (PO), and identify the predictors of misleading abstract conclusions.
METHODS: We searched Medline, Embase and the Cochrane Collaboration for reports of RCTs assessing rheumatoid arthritis, osteoarthritis or spondylarthropathies published between January 2006 and April 2008. Abstract conclusions were misleading if: the PO was not reported in the conclusion; the conclusions were based on only a secondary outcome or subgroup results; the results and conclusions were in disagreement; negative results were suggested as equivalent, or if there was no discussion of benefits and risks in cases of serious adverse events.
RESULTS: Of the 144 reports selected, we focused on the 105 articles containing a clear PO. Twenty-four reports (23%) contained misleading conclusions. Lack of PO reporting (n=10) and conclusions disagreeing with article results (n=7) were the most frequent reasons. Nineteen out of 144 (13.2%) declared study registration with clear and similar registered and published POs and no misleading abstract conclusions. Reports of negative results showed a higher frequency of misleading conclusions as did those assessing osteoarthritis. On multivariable analysis, only negative results predicted misleading abstract conclusions (OR=9.58 [3.20-28.70]).
CONCLUSIONS: Almost one-quarter of these RCT in rheumatology had misleading conclusions in the abstract, especially those with negative results.
related content
Specifically regarding Mathieu 2012:
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
- Common interventional procedures for chronic non-cancer spine pain: a systematic review and network meta-analysis of randomised trials. Wang 2025 BMJ.
- Gabapentinoids and Risk of Hip Fracture. Leung 2024 JAMA Netw Open.
- Classical Conditioning Fails to Elicit Allodynia in an Experimental Study with Healthy Humans. Madden 2017 Pain Med.
- Topical glyceryl trinitrate (GTN) and eccentric exercises in the treatment of mid-portion achilles tendinopathy (the NEAT trial): a randomised double-blind placebo-controlled trial. Kirwan 2024 Br J Sports Med.
- Placebo analgesia in physical and psychological interventions: Systematic review and meta-analysis of three-armed trials. Hohenschurz-Schmidt 2024 Eur J Pain.