The essential ingredients for conducting a randomized
clinical trial are rather simple.
First you start with a research question that is hopefully
feasible, interesting, novel, ethical and relevant. Then you come up with a
hypothesis, null hypothesis and a primary outcome measure.
Next try to determine the smallest clinically meaningful difference
that you think would be important to detect. Power your trial accordingly, get
ethics approval and off you go!
Did this “RCT” do any of this?
No.
Well, I guess they did do the “off you go” part.
This paper is so brilliantly
awful that I will not discuss any of the results or conclusions as they are
really irrelevant. However, I will
focus on a few details.
This trial was conducted in three “clinics” in Turkey.
Patients were evidently randomized (although there was zero mention of how they
were randomized… not to be pedantic but this is important) to one of three
arms; IM diclofenac, acupuncture, or intravenous acetaminophen (paracetamol). There
was no primary outcome measure but they reported all kinds of measures over
time on a VAS and VRS.
As mentioned previously, there was no power calculation performed
but they managed to enroll about 40 patients in each arm. It doesn’t take a
rocket scientist to conclude that they could only ever find very large differences
with these small numbers (probably about 60mm on a VAS). In statistical speak, the
possibility for type II error is huge.
Another question is ethics.
I do not believe that a Human Research Ethics Committee
(HREC) in Australia would have approved the experimental design of this study. Before
asking participants to take on some form of risk, pain or inconvenience, one
needs to know if the study is designed to answer the research question. Otherwise
it is a waste of time and exposes volunteers to unnecessary harm. This trial
had no power calculation, no idea if it could answer any questions and as such
could not be considered ethical.
Well done studies looking at acupuncture show that it is no
better than placebo. (These are often conducted using sham acupuncture.) When
we have an established treatment that is known to be effective, is it ethical to randomize
a patient into a study arm that is placebo? For the methodology nerds,
there was no clinical equipoise. This is mandatory before conducting an ethical
randomized clinical trial.
There is so much more we could criticize about the methods,
statistical analysis, bias’ and completely irrelevant discussion, but what’s
the point.
Unfortunately a popular and generally well regarded
educational program, EMRAP reviewed
this paper and completely missed. It goes to show that even the best
educational programs will get it wrong sometimes.
How did this paper get published? Not to be harsh, but this
publication is not exactly a high impact journal. The process for peer review
can be rather hit or miss in some of these fringe journals. In this case, it
was a big miss.
Covering:
Keynar M, Koyuncu F, Buldu I, et al. Comparison of the efficacy
of diclofenac, acupuncture, and acetaminophen in the treatment of renal colic. Am J Emerg Med 2015;30:749-53.
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