“There is a ton of chiropractor journals. If you want evidence then read some.”
This was the comment by a defender of chiropractic to a recent post of mine. And it’s true, of course: there are quite a few chiro journals, but are they a reliable source of information?
One way of quantifying the reliability of medical journals is to calculate what percentage of its published articles arrive at negative conclusion. In the extreme instance of a journal publishing nothing but positive results, we cannot assume that it is a credible publication. In this case, it would be not a scientific journal at all, but it would be akin to a promotional rag.
Back in 1997, we published our first analysis of journals of so-called alternative medicine (SCAM). It showed that just 1% of the papers published in SCAM journals reported findings that were not positive. In the years that followed, we confirmed this deplorable state of affairs repeatedly, and on this blog I have shown that the relatively new EBCAM journal is similarly dubious.
But these were not journals focussing specifically on chiropractic. Therefore, the question whether chiro journals are any different from the rest of SCAM is as yet unanswered. Enough reason for me to bite the bullet and test this hypothesis. I thus went on Medline and assessed all the articles published in 2018 in two of the leading chiro journals.
- JOURNAL OF CHIROPRACTIC MEDICINE (JCM)
- CHIROPRACTIC AND MANUAL THERAPY (CMT)
I evaluated them according to
- TYPE OF ARTICLE
- DIRECTION OF CONCLUSION
The results of my analysis are as follows:
- The JCM published 39 Medline-listed papers in 2018.
- The CMT published 50 such papers in 2018.
- Together, the 2 journals published:
- 18 surveys,
- 17 case reports,
- 10 reviews,
- 8 diagnostic papers,
- 7 pilot studies,
- 4 protocols,
- 2 RCTs,
- 2 non-randomised trials,
- 2 case-series,
- the rest are miscellaneous types of articles.
4. None of these papers arrived at a conclusion that is negative or contrary to chiropractors’ current belief in chiropractic care. The percentage of publishing negative findings is thus exactly 0%, a figure that is almost identical to the 1% we found for SCAM journals in 1997.
I conclude: these results suggest that the hypothesis of chiro journals publishing reliable information is not based on sound evidence.