Monday, July 11, 2011

Dr Kenzo Kase and Kinesio tape - The Observer advertorial enters an evidence-free zone

Once more unto the podcast, dear Friends, once more - Righteous Indignation Episode 95 to be precise, pretending to know something about philosophers and assassinating pathetic evidence presented by the Observer as proof that Dr Kenzo Kase's Kinesio tape does anything apart from make you look like you've been in a fight with some acid-tripping sellotape.

The dialogue is greatly enhanced with Marsh and Hayley's inputs, so, um, I would listen to the podcast rather than read the notes, but if you insist here is my crib sheet. For some reason (I'm looking directly at you Hayley), the first line is missing in the edit, but some brightly coloured tape should sort that out.


Last Sunday, The Observer published an article by Tim Lewis titled:
Dr Kenzo Kase: My magic tape can aid injured muscles

with the byline,
Whether in garish pink or tasteful beige, Kinesio tape provides pain relief for sports stars. And it works on dogs, says Japanese chiropractor Dr Kenzo Kase.

Whenever I read an article that talks about a “magic cure” I tend to think about “magic beans” – when the strapline contains the word "chiropractor", you know you’re going to in for a bumpy ride on well trodden path of dodgy claims, weak evidence and celebrity endorsement.

It’s fair to say that at this point I was expecting to see PowerBalance mentioned, as Kinesio tape could favourably be described as being from the same marketing stable - relying heavily on high profile sportstars to promote their products - David Beckham, Lance Armstrong and Serena Williams are amongst the many that have been spotted with the brightly coloured tape in trademark designs on various parts of the body, supposedly to help the muscles.

The original idea behind the tape (now removed from the UK website) was that the adhesive used was in a particular waveform which “microscopically lifts the skin”. Or as Krazy Kenzo states in the article
“Your pain sensors are located between the epidermis and the dermis, the first and second layers of your skin, so I thought that if I applied tape to the pain it would lift the epidermis slightly up and make a space between the two layers.”

Basic mechanics makes it clear this is nonsense – imagine you have a ham sandwich. Actually, sorry Hayley, just for you imagine it is a cheese sandwich, and you’ve just placed the second piece on top. Now if I give you some sellotape, can you put a strip on the bread so that it lifts it slightly from the rest of the sandwich? No. This, as the kidz on twitter say.

Also in the article he goes on to talk about jetlag and how it’s due to the fact that
“we are at very high altitude and that causes our body temperatures to go up”.

Now that is clear, unequivocal nonsense.

The reason why we have jetlag is because when we fly to a place in a different timezone, our circadian rhythms are all on the wonk, and our bodies want to go to sleep even though it’s only midday. Someone on a flight from UK to South Africa will not experience jetlag, because although it’s an 11 hour flight it only crosses one time zone, and so your body won’t think everything has gone to cock. The fact that Krazy Kenzo is a chiropractor demonstrates that his understanding of evidence-bases is weak at best. This show has covered the fun and games with chiropractors in the UK over the last number of years with the British Chiropractic Association failing to make a case for libel over Simon Singh saying in a Guardian article that “Chiropractors happily promoted bogus treatments”.

But let’s take a second to be kind to Krazy Kenzo – maybe his theories are trash, his biomechanics knowledge laughable and understanding of air-travel in relation to timezones childish... but, maybe the products do work. Maybe he just has the wrong reasoning.

In the article he discusses some of the evidence base for his kinesio tape. I’ve put a link in the show notes to an amazing review of the evidence in the literature about Kinesio tape by @APGaylard. It might surprise you to know that there have a number of small trial studies for kinesio tape, none of which providing anything remotely close to robust evidence for efficacy. This was yet another product with maximum marketing and minimum use.

The reference in the article is to a 2008 paper which it describes as “a study of 42 people with shoulder problems which indicated that Kinesio taping offered immediate pain relief.” Wow – immediate pain relief. I think this is an excellent learning paper for people who perhaps haven’t got a strong science background and would find reading a scientific paper a bit daunting.

So at this stage, I’d like you to pause the podcast, go to the show notes, and follow the link to the PDF of the 2008 paper printed in the Journal of Orthopaedic and Sports Medicine.

Without reading the whole paper, we can pick out a few bits from the paper which are relevant and show why the paper is of little value.

Have you got it?

Good. Now I don’t want to repeat what’s been said in other places about how to run trials of things – perhaps Trick or Treatment by Simon Singh and Edzard Ernst or maybe Bad Science by Ben Goldacre can provide some enlightenment on that – but here’s a few basics:

The title:
The Clinical Efficacy of Kinesio Tape for Shoulder Pain: A randomized, Double-blinded, Clinical Trial.

You’ll see the conclusion the front page stating that Kinesio Taping may be of some assistance to clinicians....

The gold standard of trials is that it is multi-centre, randomised, placebo-controlled and double blinded – so it sounds like the trial is fairly robust, but as we’ll see, the title is writing cheques the trial can’t cash.

The first part of a paper is always the intro and background – in this case a page or so of how bloody amazing the kinesio tape is, along with suggested ways that it works and how nothing compares to it.

First thing to look at is the number of people taking part – referred to as the n number. For a small pilot trial, n is usually less than 50, and generally, an effect at this level may help confirm a hunch and suggest something interesting, but unless n>100 the results are always going to be shaky. We can see they enrolled 42 people. Not terrible for a small pilot. However we have a little quirk here – so they enrolled 42 for the trial, but they originally had 64 as eligible. That’s around 1/3 discounted for some reason – the paper explains that
“the exclusion criteria were chosen in an attempt to eliminate subjects with pathology that would be less likely to respond to the selected taping intervention”.
They were forcing a positive result, right from the start.

Let’s look at the blinding – the title states it is double blind and randomised. Both extremely important as this is a massive source of bias.
“The primary author is a certified Kinesio Taping practitioner and applied all the taping procedures.”

So it wasn’t double blind at all, in fact it turns out that the person with the vested interest in a positive result was taping both the study treatment and the sham treatment. The paper also shows photos of the sham treatment.
Can either of you spot the trial carcrash? Well it’s two things – one, it is immediately obvious to anyone which is the sham. Secondly, the sham treatment is using the Kinesio tape.

Let’s take the first point - if the administrator of the therapy or treatment knows who is getting which treatment AND the patients know, then there is no blinding, and any results obtained should be treated very sceptically.

Secondly, they are testing their own tape used one way against their own tape used a different way, which means they aren’t even testing the efficacy of the tape – not one part of title is accurate. At best they are testing different ways of using the tape, but the trial is so shoddy, that any results are effectively meaningless.

Skip down to the discussion section (the results in a nutshell were that some people who had been taped up got better and some got worse, which was similar to the sham arm. Initially the treatment arm fared better but this difference disappeared by the third day.) How to explain this?

They mention two things:
1. Improvement in control arm could have due to the tape despite intending to be a sham application
2. A strong placebo effect of taping has been noted in previous trials.

So despite choosing people who would give positive results, pretending to double-blind but not doing any blinding, not testing what they said they were testing, the results still didn’t go their way. And they reason it away by saying the tape still had some effect, but that the treatment arm worked more at the start. Depending on your level of cynicism, this is at best being confused and at worst, outright bullshit.

A crap trial, badly run, useless results, bizarre interpretation, dubious conclusion, but printed in the Observer and given by Kinesio as proof the product works. What % of people will hunt down this paper? – I’m guessing 0.001. Kinesio are so sure that the vast majority of people won’t get past the title that they have the article for free on their website.

What astounding investigative journalism – or indeed what a great way to get cheap advertising.

(Thanks to @APGaylard, @_JosephineJones, Danny Strickland (@dts1970) and @Andrew_Taylor for their twitter help.)