The question whether spinal manipulative therapy (SMT) has any specific therapeutic effects is still open. This fact must irritate ardent chiropractors, and they therefore try everything to dispel our doubts. One way would be to demonstrate a dose-effect relationship between SMT and the clinical outcome. But, for several reasons, this is not an easy task.

This RCT was aimed at identifying the dose-response relationship between visits for SMT and chronic cervicogenic headache (CGH) outcomes; to evaluate the efficacy of SMT by comparison with a light massage control.

The study included 256 adults with chronic CGH. The primary outcome was days with CGH in the prior 4 weeks evaluated at the 12- and 24-week primary endpoints. Secondary outcomes included CGH days at remaining endpoints, pain intensity, disability, perceived improvement, medication use, and patient satisfaction. Participants were randomized to 4 different dose levels of chiropractic SMT: 0, 6, 12, or 18 sessions. They were treated 3 times per week for 6 weeks and received a focused light-massage control at sessions when SMT was not assigned. Linear dose effects and comparisons to the no-manipulation control group were evaluated at 6, 12, 24, 39, and 52 weeks.

A linear dose-response was observed for all follow-ups, a reduction of approximately 1 CGH day/4 weeks per additional 6 SMT visits (p<.05); a maximal effective dose could not be determined. CGH days/4 weeks were reduced from about 16 to 8 for the highest and most effective dose of 18 SMT visits. Mean differences in CGH days/4 weeks between 18 SMT visits and control were -3.3 (p=.004) and -2.9 (p=.017) at the primary endpoints, and similar in magnitude at the remaining endpoints (p<.05). Differences between other SMT doses and control were smaller in magnitude (p > .05). CGH intensity showed no important improvement nor differed by dose. Other secondary outcomes were generally supportive of the primary.

The authors concluded that there was a linear dose-response relationship between SMT visits and days with CGH. For the highest and most effective dose of 18 SMT visits, CGH days were reduced by half, and about 3 more days per month than for the light-massage control.

This trial would make sense, if the effectiveness of SMT for CGH had been a well-documented fact, and if the study had rigorously controlled for placebo-effects.

But guess what?

Neither of these conditions were met.

A recent review concluded that there are few published randomized controlled trials analyzing the effectiveness of spinal manipulation and/or mobilization for TTH, CeH, and M in the last decade. In addition, the methodological quality of these papers is typically low. Clearly, there is a need for high-quality randomized controlled trials assessing the effectiveness of these interventions in these headache disorders. And this is by no means the only article making such statements; similar reviews arrive at similar conclusions. In turn, this means that the effects observed after SMT are not necessarily specific effects due to SMT but could easily be due to placebo or other non-specific effects. In order to avoid confusion, one would need a credible placebo – one that closely mimics SMT – and make sure that patients were ‘blinded’. But ‘light massage’ clearly does not mimic SMT, and patients obviously were aware of which interventions they received.

So, an alternative – and I think at least as plausible – conclusion of the data provided by this new RCT is this:

Chiropractic SMT is associated with a powerful placebo response which, of course, obeys a dose-effect relationship. Thus these findings are in keeping with the notion that SMT is a placebo.

And why would the researchers – who stress that they have no conflicts of interest – mislead us by making this alternative interpretation of their findings not abundantly clear?

I fear, the reason might be simple: they also seem to mislead us about their conflicts of interest: they are mostly chiropractors with a long track record of publishing promotional papers masquerading as research. What, I ask myself, could be a stronger conflict of interest?

(Pity that a high-impact journal like SPINE did not spot these [not so little] flaws)

18 Responses to What chiropractors call ‘research’ often looks like promotion to me

  • Is the question still open?
    Surely you’re being rather generous.
    I immediately thought of the YouTube clip of the US version of ‘Loose Women” where one idiot admitted she didn’t know whether the Earth is flat, then hastily tried to cover her tracks by saying that anyway she was too busy putting food on the table for her daughter to worry about such trivial matters. An answer which, apart from anything else, would seem to be rather arrogant ( do the rest of us, lazy as we are, have that much more time to waste?)

  • 18 “treatments” at $40-60,00 each, travel time, wait time, adverse side-events, and loss of any appreciable “relief” soon after the torture ceases…..THIS is some sort of “solution”? God these bastards are without conscience.
    These “therapists” of all professions are intent to prove something that is simply untrue: one person can’t “treat” away another persons pain in expensive “visits”. Never has worked and never will in my opinion.

  • As a person who occasionally receives treatment from a chiropractor, with apparent good results , I hope there will be rigorous research. I’m interested to know.

    • there is already a lot – but the totality of the most reliable evidence fails to show that it does more good than harm.

    • Your comment suggests that you have a periodic problem. Do you always visit a chiropractor or only if your problem is particularly severe? Do you always visit the same practitioner? Do you find your visits to be emotionally/psychologically supportive, or neutral – with benefits being purely physical?

      You could do a little practical research for yourself. Next time your problem returns you could try seeing a different practitioner – if you normally see the same one. If you do not have a regular Chiropractor, then you could try a different “alternative” treatment e.g. massage or some form of gentle exercise e.g. swimming, yoga, tai chi, etc or you could try meditation classes.

      Perhaps you have already tried a variety of alternative therapies and found that only chiropractic helps? In which case, you would appear to have done enough to have personally cracked it!

    • @Sherry on Thursday 01 March 2018 at 14:31

      “As a person who occasionally receives treatment from a chiropractor, with apparent good results , I hope there will be rigorous research. I’m interested to know.”

      Sherry, I suggest you research the terms, “self-limiting condition” and “regression to the mean”. If you experience back pain, as I did recently, it will go with time. I did NOT visit a chiro (or anyone else) yet I was free from pain after a short time. Sure, going to a chiro makes you feel as if you have something, however, the reality is it probably would have disappeared in the same time or less. Remember the old adage, take a pill and a cold will go after seven days, otherwise it will clear up after a week. 🙂

      • @ Frank

        Recent research indicate that for LBP, most patients will not have fully recovered after 12 months – maybe not a self limiting condition?

        Outcome of low back pain in general practice: a prospective study

        Objectives: To investigate the claim that 90% of episodes of low back pain that present to general practice have resolved within one month.

        Results: Annual cumulative consultation rate among adults in the practices was 6.4%. Of the 463 patients who consulted with a new episode of low back pain, 275 (59%) had only a single consultation, and 150 (32%) had repeat consultations confined to the 3 months after initial consultation. However, of those interviewed at 3 and 12 months follow up, only 39/188 (21%) and 42/170 (25%) respectively had completely recovered in terms of pain and disability.

        Conclusions: The results are consistent with the interpretation that 90% of patients with low back pain in primary care will have stopped consulting with symptoms within three months. However most will still be experiencing low back pain and related disability one year after consultation.

        Also see –

        This review (on LBP) concluded:

        The findings of this review indicate that the assumption that spontaneous recovery occurs in a large majority of patients is not justified. There should be more focus on intensive follow-up of patients who have not recovered within the first 3 months.

        • @AN Other on Sunday 04 March 2018 at 17:57

          Thank you, dear receptionist. You can always be relied upon to produce the comedy gold, and you don’t disappoint again.

          To show I am fair-minded, I will give you two weeks to provide the several reasons why this ‘study’ should not have been cited. Now, choof off back to the desk and asnwer the phones while you think about it.

          • @ Frank

            I think the onus is on you to explain why this ‘study’ should not have been cited. To be fair to you I will give you 2 weeks to cite recent studies to back up your point of view.

            All the best 🙂

          • @ Frank

            1 week to go! 🙂

        • Eval and management of acute low back pain. J Gen Intern Med.2001 Atlas, Deyo.
          “Low back pain is the fifth most common reason for all physician visits, and is the second most common symptomatic reason. Although back pain is a leading reason for visiting health care providers, many affected individuals never seek medical care. In a random telephone survey only 39% of persons with low back pain sought medical care”.
          “Many may not seek medical care for back pain because episodes are typically brief. For patients with acute low back pain in primary care, 75% to 90% report improvement within 1 month. Nonetheless, recent studies indicate that persistence of low-grade symptoms or recurrences are more common than previously recognized with 25% to 50% of patients having additional episodes over the following year”….Ergo Chiropractic WORKS!!? Or….what was your point??
          Perhaps 2 visits to a typical family practice is only 99.5% AS effective as 20+ Chiropractic “visits”….at 400xs the cost?
          Or perhaps 25-50% of people simply will not exercise to help improve themselves or work manual labor that limits complete pain resolution…? And which of those 2 conditions are research-proven to be improved with expensive and desultory Chiroquackery?
          Systematic reviews on “Chiropractic’s secret-scientific-procedures” ameliorating chronic low back pain are just a tad bit less enthusiastic than throwing coins (several hundred thousand) in a well. And it’s unlikely of any value for acute pain.
          Clearly the BEST choice is relying on Trent, Critical_Chiro & Abdominal-Mike to “manage” it.

    • @sherry: not that you asked, but….1st: do you ever wonder HOW your Chiropractor actually stays in business if “you” with the very occasional treatment and (only) ‘apparent good result’ is their typical patient? They would need thousands of new-patients per year to make a living given that practice-model. Chiropractic simply isn’t effective excepting via coincidence so eventually you’ll have a condition which they “can’t help” i.e. take credit for natural-healing…. and you’ll end your affiliation. So a bevy of fresh “cases” need to be continually ensnared (not that easy given the overwhelming competition AND growing public skepticism).
      However It’s very likely they use deceptive-trade-practices and bait-and-switch in a LARGE swath of the ‘other’ patients. You may be a lucky one in that they haven’t tried to coerce you into regular or “wellness” care or you just aren’t that gullible. Or VERY unlikely but possible: you may have found a DC who practices honestly (lol).
      2nd: why not bring a friend next time and video what theatrics they do to you….look them up…ask yourself “is this even plausible?”….better, show it to a DPT, biomechanic-expert, your MD or the UPS guy, and get a second-opinion as to the likelihood it has any plausibility. If it involves “muscle-challenges”, “leg length analysis”, “motion-palpation”, x-ray, farcical “posture assessment”, adjusting “guns”, Laser, “flexion-distraction” or “drop-tables” then you’re being duped by their gypsy trickery/entrepreneurial-theatrics. Oh or spinal manipulation also!
      3rd: I would bet the “treatment” (and everyone’s treatment) is virtually identical….often preceded with the “well, Sherry you’re “out” again at L5 (sacroiliac, C5 or whatever…) it seems to be a recurring problem for you, but I can get it back in and you’ll be fine….for a while”. All that’s left is the cryin’ when you have to pay 💰

  • You are underestimating the value of a chiropractic consultation. In Sydney Australia, I charge a fee of $88.

    • @Dr Michael Epstein on Friday 02 March 2018 at 23:42

      Hey Micky (not a doctor),
      Are you back in Australia? I thought you may still have been in jail in Bali, after fleecing the locals there.

      • I was hoping this time Mr. Epstein could find time to answer my question about his comment from last august regarding his management of acute abdominal pain:

        Michael Epstein on Sunday 20 August 2017 at 09:21
        Dear Frank,
        If I was confronted with a patient with acute abdominal pain, which I have and resolved very quickly after palpating its severity and determining that the pain was manageable after performing SMAT. Stay tuned to my publication of this procedure next month or in October in the Chiropractic Journal of Australia. It’s not a case report about abdominal pain management but the mechanism of the procedure itself. I look forward to your critique of this published paper. Remember, publish or perish.

        I have reminded him of my question several times and he even promised he would reply when he was less busy. Now we know at least part of the reason he keeps disappearing.

        By the way, regarding the paper he refers to in the comment referred above.
        When it showed up, it turned out to be an unusually amateurish attempt at performing and reporting research. I guess they do not teach research methodology in chiro-school?
        Part of the efforts described there were done in Bali, as a matter of fact.

  • A$88 for the medical equivalent of kicking the tires.


  • I must disagree…kicking-the-tires can sometimes be of some value.

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