Anecdata

I once tried some homeopathic pills for hay fever.  I was still at university, the grant (yes, those were the days) had reached single figures and the hay fever season was in full swing.  I needed something and the chemist I happened into had some homeopathic remedies on the shelf and they were promising two things.  Firstly they said they were cheaper.  Secondly they said they would not induce the narcoleptic state that my then current tablets would induce.  So I bought them.

A bottle rather like the one I bought but not actually the one (ask the solicitor if this is enough to avoid a lawsuit)

Guess what.  They were useless.

I still had runny eyes, itchy roof of the mouth, sneezing bouts and the rest, in the same quantities as before and, so far as I could see, there was no improvement.  So, chalk that up as one failure for the homeopathic pills.

Now, I realise, before any supporters of homeopathy get angry, that this is one anecdote. I took these things in good faith, not understanding at the time what they really were, and I had not benefit.  About the only positive was that I was not drowsy, but then my remedy for the itchy roof of the mouth (a Mars bar) also left me alert rather than sleepy. What, however, would getting a bunch of anecdotes like this together tell me about the effectiveness of these pills?

The answer is nothing.  Anecdotes are rather self selecting - those that can be bothered tell their story.  You can see this effect on websites that ask for feedback and reviews of their products.  Lots of five out of fives, lots of one out of fives, but unlikely to get that many threes.  People who are really happy (and can be bothered) and those that are really grumpy (and can be bothered) give their opinions.  The rest, they don't bother.

To ensure that you know if the treatment is effective, you have to carry out a properly controlled study, double blinded so that neither the patient nor the person measuring the effectiveness of the treatment knows who is taking the treatment or the placebo (or in some cases the current champion remedy).  You see, humans are terribly biased.  They stick up for their favourites, be they football teams, singers or politicians. Currently we are reminded of the polarisation of opinions brought by Mrs Thatcher thirty years ago, by the film The Iron Lady.  Evidence is unlikely to sway those with firm and extreme opinions one way or the other. 

Look at it another way.  My sport is cricket.  On some apparently objective measure, the England national team is the best at playing Test matches at the moment.  The fact they got soundly thrashed by Pakistan (apparently fifth best) won't alter the ratings yet.  But currently, and it pains me to say so, Australia or South Africa could be the best.  After all, their most recent results are superior to England's dismal effort this week.  But I will root for England, cheer for England and get behind them, whatever that means, when they are playing because my emotional investment in Team England is greater than my understanding of the evidence.

Or another way.  A few years back I had the chance to watch the Olympic Games from the comfort of an arm chair in North Carolina.  It was rather hard to find out how British competitors were doing because the American TV didn't want to know.  Instead, there was a heavy concentration on the men's gymnastics because a couple of US gymnasts were in with a good chance of winning.  One did, in controversial circumstances because a mistake seemed to be punished lightly by the judges.  Not that you'd realise from the commentary, because it was so blinkered in favour of the American competitor that there was no balance in the words used on screen. 

Anyway, subjective evidence is a long way down the science totem pole.  Science prefers not to use it - hopefully if a number can be measured for something then that is best of all.  Complementary medicine (CAM) often uses anecdotes, which is why people use it.  I bet most of you look at those reviews online for washing machines and new CDs and are swayed by a handful of comments.  Perhaps you should do as I do.  Read all the three star reviews - why were they so ambivalent about their goods.  After all, they paid for them.

People are quite often paying for complementary medicine so they have a vested interest in it.  My step daughter had some Chinese herbal treatment for a skin condition ten years ago.  What she got was several expensive packets of dried leaves that tasted (and smelled) awful.  She gave up after three rounds of treatment, each more expensive than the last and each containing a different set of leaves.  Her review would have been one star.  In my opinion (though I wasn't leading this expedition down the wrong road) she was ripped off.  After all, isn't the name for complementary medicine that works "medicine".

Not the mixture my step daughter took - just for illustration purposes only (check that one with the lawyers please)

There are good studies for complementary medicine, with good methodologies, good statistics and the like and generally the answer is there is no effect.  Just like my anecdote at the start.  No benefit at all.  Money down the drain.  Could have been better spent on other things.  The emotional ties (be it anti-pharmaceutical companies or pro-folk remedies) will always be strong, and there will be those that are strongly swayed by anecdotes.  But there is scientific evidence and I know which I prefer.

Finally, how could those dessicated pills have worked.  As I understand homeopathy, the "active" ingredient is diluted so strongly that it is the equivalent of about one molecule per Atlantic Ocean, or something like that.  One drop of this "solution" on an inert pill will contain no active ingredient (unless, of course, I am extremely fortunate).  But then the pill dries out.  If, as is claimed, water has a memory (evidence = nil), then how can the evaporated water leave behind its memory on the inert, mostly mineral, pill?  It can't, can it. 

Oh well.  If anyone can explain how homeopathic pills can beat the laws of physics then I would be grateful to hear those explanations.  As they say, over to you.