There are many acupuncture meta-analysis that say the same thing: poor quality studies, not compelling evidence of efficacy, better studies need to be done.
It is the manta for the pseudo=medical meta-analysis.
The one outlier is acu-whatever (acupuncture, electro-acupuncture, transcutaneous nerve stimulation, laser stimulation, capsicum plaster, an acu-stimulation device, and acupressure have all been used) at the P6 point of the wrist.
A variety of meta-analysis suggest efficacy compared to placebo
Why, of all the processes where acu-whatever has been tried an failed, would acu-whatever at the wrist be the one that would work? What is so special about the P6 point?
This week was an interesting study that sheds some light on the effects of acupuncture and placebo: Effectiveness of a placebo intervention on visually induced nausea in women – A randomized controlled pilot study http://www.jpsychores.com/article/S0022-3999(16)30415-9/abstract
In 21 patients
nausea was induced through optokinetic stimulation. On the placebo day, participants received sham acupuncture point stimulation together with positive verbal suggestions of nausea improvement. Expected and perceived nausea severity as well as symptoms of motion sickness were repeatedly assessed.
And the sham acupuncture with verbal suggestion markedly decreased not only the nausea but the expectation of nausea.
The study was small and it would have been nice to have a sham acupuncture only and a verbal suggestion only. And there is some data to suggest men and women respond differently to placebo's for nausea.
More information to suggest that the effects of acu-whatever for nausea is indeed all theatrical placebo and that investigators need to be very diligent in controlling the nature of the theater.