From Furious of Feltham

[lathany]

One of this evening's news headlines is a story about a mother whose conviction for the murder of her children was overturned. As a result of this, the BBC website produced a page commenting on the suitability of one of the witnesses, namely Sir Roy Meadow.

Now, Sir Roy belongs to a class of people who really annoy me. Being responsible for convicting an innocent woman ? No (well, actually yes, but not specifically what I'm complaining about). It is because he is a non-statistician claiming to be an expert on statistics.

This happens... far, far too often. Doctors are particularly guilty of it because the use of their own data in the field of medical statistics makes a vocal minority think they know how to interpret all the results. But the lack of statistical training really, really shows. And it gives those of us who actually work in the field a bad name.

Grrrrr.

Comments

[dr-bob.livejournal.com]

I reckon this kind of thing happens right across the range of professions. I am constantly irritated by people making ill-conceived judgements about scientific stuff; GM foods, biowarfare, MMR etc, where people with a basic grounding in science would tell what was tosh from what is reasonable. Unfortunately, most people in the media don't have a clue, so never pick up on the fallacies and errors that get propagated this way. Just like in court, there is often no-one who can pick up on inadequate knowledge or understanding.
Dr Meadow qualifies for annoying bloke in my book, beacuse as well as not understanding stats, he also clearly hasn't got a clue about genetics. It is likely that the cot death kids in the cases described all had genetic (and probably also environmental) factors that predisposed them to cot death.
And right across bioscience, statistics is a woefully under-taught (and in my case ill understood) part of data analysis.

[cuthbertcross.livejournal.com]

Hang on, Furious of Feltham, what about all those perfectly good doctors who get a bad name from the few bad apples who bandy around statistics?

(small rant follows, not to be taken the wrong way; I'm just trying to explain that it's frustrating when all "doctors" get lumped with the same brush)

I am in no way defending the deliberate misuse of emotive "statistics" that appears to have occurred in this case. However, I am constantly told that my professional duty lies in providing information to enable patients to make "an informed choice". I am very often asked for figures by my punters to help them decide what they want to do e.g. have an operation, try one particular treatment or another. I would find it really difficult to say "I can't give you the mortality rate for this operation unless I can first explain to you the full data that gave rise to this mortality rate, the number and premorbid condition of the patients involved in obtaining the figures, the confidence intervals of the actual result, and the applicability of this figure to your good self". Quite aside from the fact that many people would drift off before the end of the sentence, how can I be expected to convey such complicated concepts in ten minutes?
Answer; I can't ; and neither can most doctors. The patient asking me doesn't want to understand detailed statistics; they want a rough chance in terms they can understand.

Here is a real example, based on what I'd tell a patient with an 8cm aortic aneurism who was otherwise fairly well, and asked advice on whether he should get it repaired or not:
OK, There is a 9 in 10 chance that if your aneurism bursts, it will kill you. If we try to fix it by replacing the damaged artery with a graft, the operation has a 1 in 10 chance of killing you. However, this means that 9 in 10 people do get better after the operation. What you have to balance is whether you prefer to just wait and see what happens knowing that you could have up to 40 years of health before the aneurism bursts (but it mught be less than that, and no-one can predict how much less) , or you can take the 1 in ten risk of an operation, and if it does work then you won't have an aneurism to burst anymore. Have a think about it, talk to your wife, talk to a friend and come and see me again next week.

Does that sound too complicated?