Two articles on PainSci cite Gabay 2011: 1. Vitamins, Minerals & Supplements for Pain & Healing 2. Statistical Significance Abuse
PainSci commentary on Gabay 2011: ?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided wherever possible.
It was a bit hard to believe my eyes when I first read this abstract. On a 100mm VAS (pain scale), the treatment group was just “8.77mm happier” with their hands. With a p=.02. And then the conclusion is that chondroitin sulfate “improves hand pain”? My my, that is a lovely demonstration of the abuse of statistical significance! (See Statistical Significance Abuse.)
Basically what the researchers found is a chance that chondroitin makes a small difference in arthritis pain. It’s not nothing, but it is an unimpressive result. The authors’ interpretation is like taking the dog to the end of the driveway and saying you took him for a walk. Technically true …
~ Paul Ingraham
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.
OBJECTIVE: To evaluate the symptomatic effect of highly purified chondroitin sulfate (CS) in patients with hand osteoarthritis (OA).
METHODS: This investigator initiated, single-center, randomized, placebo-controlled, double-blind, clinical trial included 162 symptomatic patients with radiographic hand OA (ACR criteria). Inclusion criteria included global spontaneous hand pain on a 0-100 mm visual analogue scale (VAS) of at least 40 mm, and a level of functional impairment of at least 6 on the Functional Index for Hand OA (FIHOA: 0-30 scale), in the most symptomatic hand. Patients received either 800 mg CS (n=80 patients) or placebo (n= 82 patients) once daily for 6 months and were analyzed in an intent-to-treat approach. The two primary outcomes were the change from baseline to month 6 in global spontaneous hand pain and in hand function. Secondary outcomes were improvement in grip strength, duration of morning stiffness, acetaminophen consumption, and a global impression of efficacy.
RESULTS: Decrease in global hand pain was significantly more pronounced in the CS than in the placebo group (VAS: -8.7 mm, P=0.02). Hand function improved significantly more in the CS than in the placebo group (FIHOA: -2.14, P=0.008). There was a statistically significant difference between groups in favour of CS for the duration of morning stiffness and for the global impression on treatment efficacy. Evolution of grip strength, acetaminophen consumption, and safety endpoints were not significantly different between the two groups.
CONCLUSION: This study demonstrates that CS improves hand pain and function in symptomatic hand OA, with a good safety profile.
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:
- Photobiomodulation therapy is not better than placebo in patients with chronic nonspecific low back pain: a randomised placebo-controlled trial. Guimarães 2021 Pain.
- No effect of creatine monohydrate supplementation on inflammatory and cartilage degradation biomarkers in individuals with knee osteoarthritis. Cornish 2018 Nutr Res.
- The CANBACK trial: a randomised, controlled clinical trial of oral cannabidiol for people presenting to the emergency department with acute low back pain. Bebee 2021 Med J Aust.
- Relationships Between Sleep Quality and Pain-Related Factors for People with Chronic Low Back Pain: Tests of Reciprocal and Time of Day Effects. Gerhart 2017 Ann Behav Med.
- Modulation in the elastic properties of gastrocnemius muscle heads in individuals with plantar fasciitis and its relationship with pain. Zhou 2020 Sci Rep.