The discussion whether acupuncture is more than a placebo is as long as it is heated. Crucially, it is also quite tedious, tiresome and unproductive, not least because no resolution seems to be in sight. Whenever researchers develop an apparently credible placebo and the results of clinical trials are not what acupuncturists had hoped for, the therapists claim that the placebo is, after all, not inert and the negative findings must be due to the fact that both placebo and real acupuncture are effective.
Laser acupuncture (acupoint stimulation not with needle-insertion but with laser light) offers a possible way out of this dilemma. It is relatively easy to make a placebo laser that looks convincing to all parties concerned but is a pure and inert placebo. Many trials have been conducted following this concept, and it is therefore highly relevant to ask what the totality of this evidence suggests.
A recent systematic review did just that; specifically, it aimed to evaluate the effects of laser acupuncture on pain and functional outcomes when it is used to treat musculoskeletal disorders.
Extensive literature searches were used to identify all RCTs employing laser acupuncture. A meta-analysis was performed by calculating the standardized mean differences and 95% confidence intervals, to evaluate the effect of laser acupuncture on pain and functional outcomes. Included studies were assessed in terms of their methodological quality and appropriateness of laser parameters.
Forty-nine RCTs met the inclusion criteria. Two-thirds (31/49) of these studies reported positive effects. All of them were rated as being of high methodological quality and all of them included sufficient details about the lasers used. Negative or inconclusive studies mostly failed to demonstrate these features. For all diagnostic subgroups, positive effects for both pain and functional outcomes were more consistently seen at long-term follow-up rather than immediately after treatment.
The authors concluded that moderate-quality evidence supports the effectiveness of laser acupuncture in managing musculoskeletal pain when applied in an appropriate treatment dosage; however, the positive effects are seen only at long-term follow-up and not immediately after the cessation of treatment.
Surprised? Well, I am!
This is a meta-analysis I always wanted to conduct and never came round to doing. Using the ‘trick’ of laser acupuncture, it is possible to fully blind patients, clinicians and data evaluators. This eliminates the most obvious sources of bias in such studies. Those who are convinced that acupuncture is a pure placebo would therefore expect a negative overall result.
But the result is quite clearly positive! How can this be? I can see three options:
- The meta-analysis could be biased and the result might therefore be false-positive. I looked hard but could not find any significant flaws.
- The primary studies might be wrong, fraudulent etc. I did not see any obvious signs for this to be so.
- Acupuncture might be more than a placebo after all. This notion might be unacceptable to sceptics.
I invite anyone who sufficiently understands clinical trial methodology to scrutinise the data closely and tell us which of the three possibilities is the correct one.