Ben Goldacre
Saturday October 28, 2006
The Guardian
There once was a time when your biggest worry, as a paediatrician, was being lynched by a herd of illiterate tabloid readers; but if you’re Professor Sir Roy Meadow you get scapegoated by the innumerate too. First he was struck off by the GMC for giving flawed evidence as an expert witness in the Sally Clark trial. Then he won an appeal. And now, this week, he’s half lost it again.
But what if the flaws in his evidence weren’t his fault alone? In the Sally Clark case, where two children in the same family had died, Meadow quoted “one in 73 million” as the chance of two children in the same family dying of Sudden Infant Death Syndrome (SIDS). This was a problematic piece of evidence for two very distinct reasons: one is easy to understand, the other is an absolute mindbender, but if you can concentrate, for three short minutes on a Saturday morning, I can prove that you are smarter than Professor Sir Roy, the judge in the Sally Clark case, her defense teams, the appeal court judges, and almost all the journalists and legal commentators reporting on the case.
We’ll do the easy problem first: the figure itself is iffy, as everyone now accepts. It was calculated as 8543 x 8543, as if the chances of two SIDS episodes in this one family were independent. This feels wrong from the outset, and anyone can see why: there might be environmental or genetic factors at play, both of which would be shared in the same family. But forget how pleased you are with yourself for understanding that fact. Even if we accept that two SIDS in one family is much more likely – say, 1 in 10,000 – any such figure is still of dubious relevance.
The action is in what we do with this spurious number. Many press reports at the time stated that one in 73 million was the chance that the deaths of Sally Clark’s two children were accidental: that is, the chance that she was innocent. Many in the court process seemed to share this view. The factoid certainly sticks in the mind. But this is an example of a well known and well documented piece of flawed reasoning known as the “Prosecutor’s Fallacy”.
Two babies in one family have died. This in itself is very rare. Once this rare event has occurred, the jury needs to weigh up two competing explanations for the babies’ deaths: double SIDS or double murder. Under normal circumstances – before any babies have died – double SIDS is very unlikely, and so is double murder. But now that the rare event of two babies dying in one family has occurred, the two explanations – double murder or double SIDS – are suddenly both very likely. If we really wanted to play statistics, we would need to know which is relatively more rare, double SIDS or double murder.
Not only was this crucial nuance missed at the time, it was also clearly missed in the appeal: they suggested that instead of “1 in 73,000,000″ Meadow should have said “very rareâ€. They recognised the flaws in its calculation – the easy problem above – but still accepted it as establishing “a very broad point, namely the rarity of double SIDS.” But that was wrongheaded, and rarity is irrelevant, because double murder is rare too. The appeal court thought Meadow had maybe got the number of millions wrong, when in fact the precise figure was a side issue: and an entire court process failed to spot the nuance of how the figure should be used.
Twice.
If it is true that Meadow should have spotted and anticipated the problems in the interpretation of his number, then so should the rest of the people involved in the case: a paediatrician has no more unique responsibility to be numerate than a lawyer. The Prosecutor’s Fallacy is also highly relevant in, for example, DNA evidence. Anyone who is going to trade in numbers, and use them, and think with them, and persuade with them, and lock people up with them, also has a responsibility to also understand them, and as you’ve just seen it’s hardly rocket science. But paediatricians aren’t just lynched by the illiterate herd: in this case, one was scapegoated by the innumerate.
Another way of looking at this interesting problem is…
Let’s say you come across two arrows stuck in a wall, a millimetre apart. I am standing next to the wall with a bow and arrow looking well pleased with myself. Am I a good archer? Your answer depends on the context. If there is one target drawn on the wall, and it was drawn before I got there, and I fired my two arrows dead into the centre of the bullseye, then there is little doubt that I am a total gangsta.
If, on the other hand, the wall is massive, and filled with tens of thousands of arrows that I’ve been firing into it over the course of many years, then the fact that there are two adjacent arrows here and there is not headline news. If I came along and drew a target around the two that are close together, you wouldn’t congratulate me on my archery skills.
That, I’ll say it again, is the irrelevance of the one in 73 million figure, even if it were a valid estimate.
kim said,
November 1, 2006 at 5:50 pm
There was one incident. It was six years ago. We don’t even know that the people concerned actually confused paediatrician and paedophile: that was the best guess of the paediatrician concerned. For all we know it may have been a case of mistaken identity. (See news.bbc.co.uk/1/hi/wales/901723.stm for more details.)
But then, the incident gives lots of people the opportunity to feel smug and morally superior to tabloid readers, and I guess that’s all that matters.
doctormonkey said,
November 1, 2006 at 7:18 pm
going all the way back to #34 and #35…
not only have lawyers maintained their self-regulation but one of the cornerstones of the attacks on the medical profession’s professionalism has been from the (lawyer) at the head of the Shipman Inquiry (Dame Janet Smith) who appears to have gone on a self-appointed, government funded witch hunt/jihad. the thought that occurs is sort your own mess out legal-types!
in terms of expert witnesses, particularly if you pay, i think you can find an “expert” who would say almost anything: historians who deny the Holocaust, scientists who deny evolution etc
and on a more topical note, it is nice to see the loophole-lawyer (Nick Freeman) get nicked, even if he hasn’t done anything, just on as a point of principle (and well done the psychic Dr Aust)
#43 Dr Aust comments that lawyers get paid irrespective of the outcome of a case but for their time – so do doctors, we are not ill, we do not care (personally) for the patient, we attend because we are paid to. i have heard stories of medicine from China where doctors were paid only when patients got better but this may be apocryphal (certainly scary for palliative care doctors…)
Dr Aust said,
November 1, 2006 at 7:49 pm
Hi Dr M.
I think Drs being paid for time (cf lawyers) is a fair analogy with PRIVATE medicine, where the Dr is billing separately for every consult. Then it clearly does resemble the lawyers’ set-up, as the patient (or insurance) is charged for every last bit, more service (no matter how small), more money. For instance, when I had a minor op privately a few yrs back the general surgeon’s fee for the initial
Dr Aust said,
November 1, 2006 at 7:58 pm
Oops… dunno what happened to the rest of that post…
…fee for initial (well under 10 min) consultation was £ 130, fee for a look-see a week after minor op to chek healing £ 70 for under 2 min. All plus the operation cost.
Being a 9-5 salaried lifer is a bit different.
What I was really getting at was that, in e.g. a negligence case, only the lawyers were being paid for every service delivered – per hr worked, per letter sent etc. More tiem into it, more pay. The Dr being sued and anyone else making witness statements would be just adding it to their regular work.
For instance, last time Mrs Aust was involved (giving a statement) in a medical negligence case she spent a good 10 hrs reviewing notes and documents, clarifying and explaining terms and matters of medicine (for the lawyers), making a statement, correcting statement etc etc. All at home, all for no payment, she hadn’t worked for the Trust in the case for several years. All done as “professional courtesy”. Would have been even more time had the case gone to court.
Dr Aust said,
November 1, 2006 at 8:03 pm
A further thought:
Surely the people MOST analogous to lawyers in terms of their “hired gun” role vis-a-vis most of us are those 90s-and-noughties uber-successes the (management) consultants?
External to the organisation, charge by the hour, large rates, everything is chargeable (to the last lunch/paperclip/taxi), make you spend your time explaining your job to them (with the meter running) so that they can tell you (based on their larger brain power and “blank sheet of paper” approach) how you SHOULD be doing it etc etc.
doctormonkey said,
November 1, 2006 at 8:16 pm
Dr Aust:
just had an interesting evening with a small group of other intelligent West London private school educated, masters graduates about management consultancy as many of our friends are such creatures. on balance they are about as bad as the lawyers from our year at school too. i am the only medic in the group (the others all took longer over their courses or gap years or both).
i agree that the analogy to medicine is more that of private medicine than NHS although could the NHS be compared to the CPS (agghhh God NOOOOoooooo……) or the american style state defenders? buying doctor or lawyer time collectively. another group that occurs are the Treasury Solicitors who are the civil service/government lawyers.
i do think that it is disgusting the amount of effort that people have to put in when there are cases, such as the one you mention Frau Doctor Aust beinginvolved in, when they are not paid for it – curious what would happen if a doctor attempted to bill the lawyers or their clients directly? i suppose the question would be which to bill but you could always bill both if it is a statement (both will use it) or the ones who ask for an opinion (as only one will use it) and bill by the hour (1 hour minimum).
i may start to look at law conversion degrees… self regulation and seemingly a license to print money although would lose some benefits like ability to stab people (with a needle) with less chance of police coming after me!
Dr Aust said,
November 1, 2006 at 10:29 pm
Yes, converting to become a lawyer is something I hear a lot of my medical acquaintances joke about, although I have only known one doctor who actually did it. He was a surgeon, BTW, so for him to jump ship the potential financial rewards of lawyering must have looked seriously Big League (slight joke).
Even Mrs Dr A has muttered occasionally about doing the law conversion thing, with the usual bitter gags about reading the case notes just the same as now but being able to bill the reading time at £ 150 / hr.
A more serious point about this is, I guess, the one about the death of the old “professionalism” which these sorts of discussions raise. This applies to many many public sector jobs – medicine, teaching, academia, social work etc. People used to feel it was part of the “unspoken contract” to go the extra mile, work 90 min past the shift end or handover, read stuff in the evenings, do out of school clubs, and so on. But with the rise of the centrally-imposed targetting, and the nitpicking clipboard-toting oversight bureaucracy that goes with it, people increasingly take the view that if you want extra hours done you can !*!”ing well pay for them.
doctormonkey said,
November 1, 2006 at 11:48 pm
re: professionalism (#57) and slightly off topic
i think i lost the inclination to “go the extra mile” when working rotas that were borderline illegal or dubious in their “banding” (banding is the supplement paid to account for the length of or anti-social nature of extra hours over a normal working week of Monday to Friday, 8-7) and so i felt that if they wanted to abuse me like this then they (they = “management”) would not get extra work out of me if they were avoiding paying me for this time/work
elder_pegasus said,
November 2, 2006 at 9:49 am
dragging right back to the original point, I’ve dug out the bmj article on the original decision to strike him off…
worth noting… “Mary Clark-Glass, chair-woman of the GMC’s fitness to practise panel, told him he had undermined public confidence in doctors who play a pivotal role in the criminal justice system as expert witnesses.” – it seems entirely fair that he was accused of this given that he not only produced the irrelevant and dodgy statistics himself, he seemed to have made no effort to retract them (anyone able to contradict that, please do)
The article also notes (annoyingly without details or source) “that a cot death is more likely than murder” – if that’s true, there’s the relevant statistic.
Although the whole notion of convicting or otherwise based on statistical probability seems somewhat incompatable with “beyond reasonable doubt” anyway…..
stever said,
November 2, 2006 at 9:34 pm
All very interesting.
My recolection – no doubt twisted by crap media reporting was that Meadows saw the news story on Tv and approach the police of his own volition saying he was convinced it was mnurder, with no evidence beyond the TV story. i thought that was why he got struck off.
Alvin said,
November 3, 2006 at 8:26 am
Ben, thank you for the nice discussion on this topic and your input. Though I agree with you that indeed the should also be shared by the judge, lawyer, jury, and Meadows himself, I do not think that Meadow was the scapegoat in this situation. Sir Roy Meadow was hired as an expert witness to this case. His credibility is based on his expertise in this area and when asked a question in the case, he is expected to give valid information. When he quoted the “1 in 73 million” figure, he is idirectly giving false information to the case and in turn affected the outcome of the case. Because he is an expert int his area and his expertise was relied on heavily for the conviction of Sally Clark, he should hold full resonsibility for his action. Had he not quoted that figure, the outcome of this case could have been different.
petey said,
November 3, 2006 at 9:22 am
Ben said “But now that the rare event of two babies dying in one family has occurred, the two explanations – double murder or double SIDS – ”
There are another 2 scenarios – one murder and one SID, either one being the first event.
Alvin said,
November 3, 2006 at 9:34 am
Quote “29 billgibson said:
October 30, 2006 at 2:03 pm
My neighbour the forensic pathologist calls expert witnesses “liars for hireâ€. They aren’t independant, each one is paid by one side to give an opinion.
———–
Though I do see that there is potential for expert witnesses to give biased opinions, one may also say that both sides can get their own expert witness. Moreover, the court could also be hiring its own witness for the case to make sure the information is valid. Being an expert witness also mean that your expertise is your credibility and qualifies you to give your testimony in the court. If one fails to do that or give biased opinions they will be punished legally and loses their credibility as an expert witness – an example would be Sir Roy Meadow.
apothecary said,
November 3, 2006 at 10:39 am
Lots of medics/pharms/nurses are innumerate. Big Pharma is another player that makes hay with this – quoting eg relative risk reductions in its marketing. Doing a brief presentation to some SpRs and consultants, pointing out that for any relative risk reduction, the absolute risk reduction depends on the baseline risk (durr!) it was truly frightening how many had never thought about that before.
But as RS said back at 5, we need to be a lot more Bayesian. At best, that is what a criminal trial should be – lots of small pieces of evidence which, on their own, may not have huge positive or negative likelihood ratios, but put together give us a pretty good negative or positive predictive value. Omitting evidence like the possibility of infection – which would have had a reasonably strong negative likelihood ratio wrt foul play – was IMVHO at least as bad as attempting to quantify a risk far better expressed as “very rare”.
Dr Aust said,
November 3, 2006 at 3:15 pm
stever wrote:
“My recollection – no doubt twisted by crap media reporting was that Meadow saw the news story on Tv and approach the police of his own volition saying he was convinced it was murder, with no evidence beyond the TV story. i thought that was why he got struck off.”
You’re confusing Roy Meadow with Professor David Southall, who is the paediatrician this story applies to, steve – see:
news.bbc.co.uk/2/hi/health/3538320.stm
bmj.bmjjournals.com/cgi/content/extract/329/7462/366-a
Southall was not struck off, but was reprimanded and had restrictions placed on his work.
RS said,
November 3, 2006 at 4:50 pm
“…we need to be a lot more Bayesian. At best, that is what a criminal trial should be”
Although you want to avoid one of the majore flaws in Bayesian reasoning, the use of arbitrary subjective probabilities, which are particularly open to abuse, as in:
en.wikipedia.org/wiki/Regina_versus_Denis_John_Adams#Use_of_Bayesian_analysis_in_the_court
Dr Aust said,
November 3, 2006 at 6:12 pm
Of course, one can view both Meadow and Southall as cautionary tales; gifted people who did important work but became so wrapped up in their theories that they could not be objective about them, and ultimately were unable to accept that they might ever be mistaken…. a very dangerous frame of mind for an expert witness.
In Southall’s case he was/is famous for his work using covert video recording in a group of children who had a history of “unexplained life-threatening events” and where the doctors suspected the parents might be responsible. In a celebrated study Southall showed using the video surveillance that in a number of these cases a parent was indeed harming the child.
pediatrics.aappublications.org/cgi/content/abstract/100/5/735
The upshot of this work was that no matter how unthinkable it was that parents might intentionally harm their own small children, to the point of suffocating them, it clearly did occur.
Of course, that it CAN happen, and sometimes does, doesn’t tell you HOW LIKELY it is to be occurring. Southall and his co-workers made this point very explicitly at the time, although you might conclude later events showed he lost sight of this.
So we are back to the begining with the questions “What are the real relevant statistics?” and “Who should be capable of working out how they are derived?”
PS It’s amazing what you can find on the net – the full High Court Judgement on Professor Southall vis-a-vis the Clark case is at:
www.bailii.org/ew/cases/EWHC/Admin/2005/579.html
doctormonkey said,
November 4, 2006 at 5:05 pm
#67 – wow Dr Aust, a magnificent link to the full High Court Judgement, I have just taken the time to read it in full and feel that it is definitely worth reading.
it has changed my understanding of the role of the GMC and such professional bodies in general which as a member of the medical register is quite important!
Robert Carnegie said,
November 5, 2006 at 2:31 pm
Message 62, Petey – Natural death of a child and child murder are both rare in the English middle class, both are somewhat liable to be repeated for siblings for various reasons, and they’re probably more-or-less independent. So it’s more likely – I don’t want to try to say -how- much more – that two child deaths in a family are both due to the same one of these causes, than that they are one of each. That’s as a probability exercise – which is not necessarily directly convertible to the legal principle of “beyond reasonable doubt”. Back to the lottery, if I buy a ticket is it beyond reasonable doubt that I haven’t won the jackpot, and, that being the case, why did I buy the ticket… And in a murder case or a lottery, in fact it either was or wasn’t. (Leaving aside that “murder” gets slippery when you claim “diminished responsibility”, but I suppose we hear that claimed much more than it’s allowed.)
And the disgrace of Professor Sir Roy Meadows does not mean that Sally Clark was not charged with a crime that she had committed. For that matter, I gather that Dr WIlliams’s final opinion was that one of the Clark children was shaken to death and one was smothered, the former being the case with the mishandled evidence of infection. That view – for whatever it’s worth – doesn’t support a similar genetic or accidental cause for both deaths,
As for future inquiries and which set of other cases should be used for any comparison… I think the set of parents with multiple infant deaths will include multiple child murderers as well as multiple natural death victims, so you couldn’t tell the difference, whereas the set of families with one death will proportionately include fewer murderers – I assume that overall there are fewer murderers – and there wouldn’t be much difference between parents who have had one child, and parents who, due to a death, have had one child at a time. But I expect families of more than one child at one time to have measurably different outcomes. Of course that will partly because, purely statistically, these children were lucky enough to be born without either a disease or a murderous parent that would do them in before the second child arrived.
I also think that parents are not from their own birth either evil people who will inevitably murder their child or normal people who will certainly not do so. Caring for an infant is incredibly stressful, women typically also have a hormone roller-coaster to deal with, and your sanity is under terrible pressure. When and whether this should or should not be a valid defence against a charge of harming a child, I consider to be lower on the agenda than arranging as much support as possible for the family so that these tragedies don’t happen.
apothecary said,
November 5, 2006 at 6:14 pm
>>it has changed my understanding of the role of the GMC and such professional bodies in general which as a member of the medical register is quite important!
Must just share this www.blacktriangle.org/blog/?p=1485 re my own professional regulatory body.
apothecary said,
November 6, 2006 at 4:39 pm
re 70. Just re-reading that, I want to make clear that black triangle is not my blog, I am not Antony Cox and was never intending that anyone would think I was. I’m 99% certain no-one would have made that misinterpretation, but just to be certain…
Dr Aust said,
November 6, 2006 at 7:00 pm
Re post 69:
Interesting points about parents, Robert.
if you take Southall’s Pediatrics paper at face value, the majority of the parents who his video surveillance found physically harming children were diagnosed (subsequently) by psychiatrists as having “personality disorders”, although this is a pretty catch-all term (includes a wide range of things, and of varying degrees of severity). From the histories given it seems clear many of these parents themselves had grim childhood personal histories, perhaps not unexpectedly.
I do agree with you generally about the strain that having kids put on everyone, though. Given the pressures I am never that surprised that some parents do hit children. The tragedy is that most parents who don’t cope well could probably be helped effectively – when one watches the TV shows like “Little Angels” and “House of Tiny Terrors” that (child psychologist) Tania Byron does, the results do seem to be quite startling, and show what a bit of good advice and support can do for parents who often appear to be at their wits’ end. As a society I think we in the UK are not very good at supporting parents, and the ones that most need the support probably are the hardest to reach, for all sorts of reasons including social exclusion.
Dealing with the kinds of cases described in some of the published papers on parents harming kids really must be a truly awful job. I have one friend who is a senior child protection social worker, and another who is a community pediatrician, and I wouldn’t do either of their jobs for any money there is.
Dr Aust said,
November 6, 2006 at 7:10 pm
Re post 69:
Interesting points about parents, Robert.
if you take Southall’s Pediatrics paper at face value, the majority of the parents who his video surveillance found physically harming children were diagnosed (subsequently) by psychiatrists as having “personality disorders”, although this is a pretty catch-all term (includes a wide range of things, and of varying degrees of severity). From the histories given it seems clear many of these parents themselves had grim childhood personal histories, perhaps not unexpectedly.
Of course, the kind of serious premeditated life-threatening harm his paper was discussing is a long way from (e.g.) a mum-at-end-of-tether slapping a screaming two yr old in a flash of anger after four sleepless nights. The abuse in the Southall paper’s cases was implied to be repeated, was rather deliberate, and was not associated with any triggering event (like screaming).
I do agree with you generally about the strain that having kids put on everyone, though. Given the pressures I am never that surprised that some parents do hit children. The tragedy is that most parents who don’t cope well could probably be helped effectively – when one watches the TV shows like “Little Angels” and “House of Tiny Terrors” that (child psychologist) Tania Byron does, the results do seem to be quite startling, and show what a bit of sensible advice and support can do for parents who often appear to be at their wits’ end. As a society I think we in the UK are not very good at supporting parents, and the ones that most need the support probably are the hardest to reach, for all sorts of reasons including social exclusion.
Dealing with the kinds of cases described in some of the published stuff on parents harming kids really must be a truly awful job. I have one friend who is a senior child protection social worker, and another who is a community pediatrician, and I wouldn’t do either of their jobs for any money there is.
Dr Aust said,
November 6, 2006 at 7:13 pm
PS Oops – sorry, two versions of the same post there, blame uploading problems. If anyone is in charge you can delete # 72.
doctormonkey said,
November 6, 2006 at 8:30 pm
clearly no one is in charge – all hail discordia, long may chaos rule (if #72 is deleted, delete this too!)
Skindoc said,
November 10, 2006 at 12:53 am
Ben,I wish I’d joined this discussion a few days ago but it has been a salutary lesson that my distaste for the Left wing politics of the Guardian has deprived me of the opinion of someone who is clearly on the side of the truth rather than that of expediency. The Truth is not what the Courts of this country are searching for but rather Justice, and there is something to be said for that. The Court has already said that it would be better to allow a child murderer to go free rather than risk the conviction of a loving parent for the murder of her child.Roy Meadow was one of the first to realise than the mother, who was his natural ally in the fight for her child’s life, might be the agent of his distress.He has been hounded, vilified and humiliated by scientifically and medically illiterate journalists and by the vilest of the legal profession who more properly deserve the title of ‘professional liers’ than do the medical experts alluded to by an earlier commment.BBC journalists transposed words blatently to further their lies and even today, with the latest Appeal by the GMC, reputable jounalists repeat the lie that Meadow was responsible for the incarceration of Sally Clark for the murder of her babies, Christopher and Harry, when, as you correctly say, it was the failure of a pathologist to put before the court pathological results which he thought were irrelevent but were not within his discretion to withhold.That these results could then be exploited to suggest that a baby who is feeding happily whilst sitting in a bouncy chair should, in the space of a few minutes whilst one parent was out of the room, succumb to an infection whose very nature is its slow malevolence, a little child with muliple injuries including bleeding into the brain and spine ,is to realise that our system, whatever else it does, does not speak for the baby whose last minutes might not have been spent in the tender care of its mother but in dreadful pain at her hands.Sally Clark was convicted of murder on the evidence before the jury of damage to both her dead children.The evidence of Meadow, the infamous evidence of Meadow, the evidence used by the egregious lawyers to attempt the liberation of any convicted of murder to whom could be linked his name was of no importance, because, as you have already said, it was irrelevent to the case and was only introduced because the Defence were assumed, erroneouly, to be basing their case on the supposition that the deaths were SIDS.Any competent Defence team would counter with an immediate question as to the likehood of double murder or even have introduced their own expert but they didn’t because they had decided that the deaths could not possibly be so classified.They were not Meadow’s statistics but the results of the statistician’s analysis of the nationwide survey into cot deaths over many years.What these figures show is that if you are a middle class affluent family who don’t smoke, and are of a certain age, then your chance of having two cot deaths is very very rare indeed.I haven’t been able to find any such cases in the last decade and more, so we are getting to the time when Meadow’s(the survey’s) figures may well be more accurate than his detractors might wish .He certainly was inept with his colouful metaphors to exlain probability to the jury but to have struck him off was an act of consumate cruelty made by a Fitness to Practise Committee who I ,and many of my colleagues in Medicine, thought deeply shameful.I asked that Mrs Clark-Glass and the others castigated for their incompetence by Judge Collins in Meadow’s appeal should resign from any futher practise that might allow then to sit in judgement of their betters.They declined to do so.We still have reports that Sally Clark was’wrongfully’ found guilty when she was quite properly found guilty by a jury on the evidence of the circumstances of the deaths of the children and the nature of their injuries.Her second Appeal was allowed because of missing pathology reports which were used as the basis of a medically preposterous suggestion that a healthy baby up and died from an infection in the space of a few minutes.The allowing of an Appeal does not carry with it a presumption of innocence. Children are killed by their parents.They always have been and they always will be.Someone has to speak on their behalf . Meadow did and look where it got him.
biker said,
November 12, 2006 at 6:24 pm
Wow! All that without drawing breath! And, may I say, totally missing the point. (#76)
My twopenneth, which I’ve thought since first following the trial, is that Prof Meadows is guilty of serious misconduct and should be struck off..
Whether his “evidence” was crucial or irrelevant is not the point. Neither is the accussed’s guilt or otherwise. Nor the incompetence of the defence in not questioning the testimony.
He was in a position of authority, intended to be trusted by the jury as such. He had a duty to be sure he knew what he was talking about, yet he clearly did not. Forget even the prosecutor fallacy; what he asserted was clearly wrong to anyone with an O level in maths. If he did not understand basic statistics, as he clearly did not, then he had no right to quote them, indeed he has a duty NOT to. In short, he strayed outside his area of expertise, but allowed others to believe he had not done so, whilst giving potentially crucial testimony. THAT is what is unforgivable.
The blatant error which was obvious to me from the start is that, in the real world, outside theoretical coin tosses etc, the fact that someting has occurred once, can strongly influence the chance of it happening again, (whether because of genetic factors, environmental causes, a child murderer living next door, etc ). Prof Meadows has to assume SIDS is a totally random event in order to ignore these factors, in order to draw his conclusions. (Unless we now know definately, irrefutable and without exception, the cause of SIDS. And unless you doctors are keeping it to yourselves, I don’t think we do, do we?)
If the statistic was supplied by a statistician, then it is surely his role as an expert witness, to factor in the real world to the analysis, not to ignore it. This is a schoolboy error and is frankly, inexcusable.
(I should add that everything I know about the case comes from news reports, so if I myself am talking B*****s about the detail, I stand to be corrected)
BTW, fascinating original article. The “Prosecutors Fallacy” had never occurred to me before. (Unless I’ve just described it in a different way above. But I don’t think I have…)
Keep up the good work, Ben. I’m right behind you all the way, even if this – my first – posting is actually disagreeing with you about the scapegoating aspect. But then, I’m not a doctor 🙂
Dr Aust said,
November 14, 2006 at 10:00 pm
If anyone is not completely fed up with this subject there is what seems to me to be a a mostly sensible account covering Roy Meadow and his expert witness work, including the Clark case, on wikipedia:
en.wikipedia.org/wiki/Roy_Meadow
There is also a press release issued after Sally Clark’s first (failed) appeal trial by the Royal Statistical Society, commenting on evidence consisting largely or entirely of statistics:
www.rss.org.uk/docs/Royal%20Statistical%20Society.doc
Finally, for a recent medical take (not too hard to read) on the whole issue of child protection, which sheds light on why many paediatricians have some sympathy with Roy Meadow, see the review in the Journal of the Royal Society of Medicine at:
www.jrsm.org/cgi/content/full/99/1/6
Steiny said,
November 18, 2006 at 9:02 pm
Hi Ben,
I had such a good time chatting last night that I thought I’d pay you the highest form of compliment I am capable of, namely by reaching down from my ivory tower to attack you for promoting the sort of myth you so rightly scorn when done by others.
The crime of which you are accused is in the very first line of the above article:
“There once was a time when your biggest worry, as a paediatrician, was being lynched by a herd of illiterate tabloid readers”
A good introductory gag, no doubt. Made me smile, in fact. But it is a gag based on a story which has done a good bit to fuel the idea the that once someone is accused of pedophilia the average British community will always hound them to their dooms, no matter how absurd or false the accusation. One gold star for a good choice of investigative topic for Brendan O’Neill, one trip to stand in the naughty rumour circulating corner for Ben 🙂
news.bbc.co.uk/2/hi/uk_news/magazine/4719364.stm
ta ta,
Tom
Ben Goldacre said,
November 18, 2006 at 10:23 pm
fly moves steinberg. not only do i know brendan’s article, i half-heartedly tried to track down yvette coete, the doctor, for an interview, through a mate on a paeds rotation out west, sadly without success. she was a paeds SpR, i think, not a consultant, if i can lower myself even further into glorious pedantry and gently chide brendan in turn. so guilty as charged, i propagated it knowingly, as an in joke with myself, and for that reason i specifically said it was a worry, not a fact, because of course spreading fear is our business.
Geoff_S said,
November 24, 2006 at 11:06 pm
There’s an interesting lecture by Peter Donelly on the Technology Entertainment design (TED) site in which he gives a very good explanation of statistical errors in the prosecution’s arguments in the Sally Clarke SIDS case.
Look here:
www.ted.com/tedtalks/index.cfm?flashEnabled=1
There’s lots of other interesting stuff there too.
Geoff
jiangjiang said,
December 8, 2009 at 2:40 am
ed hardy ed hardy
ed hardy clothing ed hardy clothing
ed hardy shop ed hardy shop
christian audigier christian audigier
ed hardy cheap ed hardy cheap
ed hardy outlet ed hardy outlet
ed hardy sale ed hardy sale
ed hardy store ed hardy store
ed hardy mens ed hardy mens
ed hardy womens ed hardy womens
ed hardy kids ed hardy kids ed hardy kids