Archive for May, 2008

The “toxins in vaccines” crowd are still with us

May 29, 2008

Rather depressingly, the anti-vaccinationists, those Never-say-die Energizer Bunny types of the Alt Reality fraternity, are back for another round.

As a lot of Bad Science-aware people will already know, American surgeon-blogger Orac, of Respectful Insolence blog fame – and bete noire of the vaccines-cause-autism lobby – has been writing about the imminent UK arrival (well, next week) or American writer and darling of the anti-MMR vaccine crew, David Kirby. It turns out that Kirby is not just doing some book–signings and the odd lecture; he is also down to give a briefing in the Houses of Parliament, no less. To quote Orac:

“My British readers, say it ain’t so! Hot on the heels of learning that, bankrolled by antivaccinationists, David Kirby is planning a trip to the U.K. in early June, I find out something even more disturbing.”

Orac then reproduces the following press release:

From: “Clifford G. Miller”

May 23, 2008 — CONTACT: David Kirby –


Briefing by Journalist Who Covers Vaccine-Autism Debate is Sponsored
By Lord Robin Granville Hodgson, Baron Hodgson of Shropshire

U.S. Journalist David Kirby, author of the award winning book “Evidence of Harm, Mercury in Vaccines and the Autism Epidemic – A Medical Controversy,” will give a special briefing on this debate at the Houses of Parliament in London, on Wednesday, 4 June.

Mr. Kirby will speak about recent legal, political and scientific developments in the United States in the ongoing vaccine-autism controversy. The briefing is open to Peers in the House of Lords, Members of Parliament, their Staff, members of the Media, and Invited Guests.

The briefing will take place on Wednesday, 4 June at 3:30PM at the Houses of Parliament, Palace of Westminster, Committee Room 4. It is being sponsored by His Lordship Robin Hodgson, Baron Hodgson of Astley Abbotts, Shropshire.

In addition to his Parliament briefing, Mr. Kirby will also give a free public lecture on Wednesday 4th June, 6:30-10PM at Regent Hall, 275 Oxford Street, London.

Hmm. A number of things spring to mind.

First, Kirby’s book may be “award-winning”, but it has very definitely not been winning science awards. Orac has written scathingly about David Kirby’s (mis) understanding and (mis) use of scientific evidence.

Second, Kirby is frequently billed in articles or press releases as a “former New York Times contributor”. This is strictly factually correct as written, but conceals the fact that Kirby was not a science or health correspondent for the venerable NYT. He was actually a travel writer.

A more specific question for us UK geeks would seem to be how Lord (Robin) Hodgson, the peer sponsoring the event and a real Tory grandee, is connected to David Kirby. Hodgson has no track record on health issues, as his key Shadow “portfolios” for the Conservative Party in the Lords have been Trade and Home Affairs.

Where is the noble Lord coming from?

I had written a long discussion on this, but as I was about to post it I saw that noted autism blogger Mike Stanton had beaten me to it over on his excellent Action for Autism blog. So rather than repeat what he has said, please pop over there and read his discussion of Lord Hodgson’s views on vaccines, as expressed in a House of Lords debate back in Feb 2003.

To cut to the chase, Hodgson has a son diagnosed with mild Attention Deficit Hyperactivity Disorder (ADHD). Like many parents with kids with ADHD or autistic spectrum disorders (ASD), he has felt dissatisfied with the mainstream treatments on offer and become interested in alternative therapies. However, he has also seemingly bought some of the anti-vaccine lobby line:

“It is unlikely that there is any one single cause [of ADHD]. Genetics and heredity will probably be found to play a significant part. But what other factors are in play? One matter looks increasingly likely to be a significant contributory cause: the requirement in this country that every baby receives three injections in the first 16 weeks of life as immunisation against diphtheria, tetanus and whole cell pertussis—whooping cough, to laymen—(DTwP). As I understand it, each standard dose of the vaccine used in the UK contains 50 micrograms of a substance called thimerosal. Each dose of thimerosal contains 25 micrograms of ethylmercury. Mercury is a highly toxic substance. That means that, by the 16th week of life, every baby in this country, with an inevitably fragile immune and nervous system, has been injected with 75 micrograms of ethylmercury…”

This would explain the Hodgson – Clifford G Miller – David Kirby connection: as even a cursory squint at Clifford G Miller’s website will show, he is a long-time anti-vaccine campaigner, and serial haunter of the BMJ electronic comments threads on the topic.

But… the vaccines don’t have mercury in any more

The problem for Kirby and other thimerosal aficionados – including British psychologist and author Lisa Blakemore Brown, who Hodgson also mentioned in his speech, and who seems to have played a part in Kirby’s upcoming UK tour – is that the thimerosal theory is on its last legs. This is mainly because even once thimerosal was removed from the vaccines – which happened in September 2004 in the UK – ASD diagnosis rates have not dropped. Hence, as Orac has again noted, the move to blaming ill-defined ”Toxins”.

[PS – the MMR vaccine, contrary to the urban legends, never contained thimerosal. If you want to read more about thimerosal there is an old (2003) NHS factsheet here (NB – pdf). And the lack of effect of removing thimerosal from infant vaccines on autism rates has been shown by large studies in Denmark, Canada and the USA, all of which stopped using thimerosal earlier than the UK did.]

Given these facts, it is hard to disagree with Orac’s view that it isn’t mercury, or toxins that really matter – for these people ”It’s All About the Vaccines”

And why now?

A further interesting question is: what has re-activated Lord Hodgson’s interest now?

Since UK politicians are infinitely more sensitive to what is going on in politics – including US politics – than to what is going on in science, one wonders if this isn’t in some way a knock-on effect of the rather ambiguous remarks some of the US Presidential candidates have been making about an autism “epidemic” (see Orac posts passim, for instance here). Indeed, the press release that accompanies David Kirby’s visit specifically makes this connection in a later section.

Orac has detailed how all the US presidential candidates, plus ex-President Bill Clinton, have been making depressingly ambiguous – not to mention scientifically inaccurate, and even disturbingly stupid – statements about autism and its possible causes. Many bloggers think the candidates should sack their science advisers, although perhaps we should sit tight and just put it down to electioneering politicians’ desire not to put off a single potential voter, no matter what way-out things the voter might believe.

However, let’s hope whichever of the US candidates does gets elected in November can find proper science advisers once in office, rather than being swayed by celebrity nitwits like Jenny “I read it on Google” McCarthy. There should be a few folk round the National Institutes of Health (NIH) and the Centres for Disease Control (CDC) that can direct them to suitable people.

And closer to home, let’s hope Lords and MPs give David Kirby’s blusterings the wide berth they deserve. Or perhaps even better, let’s hope some of the science and medicine-literate Lords and MPs can be persuaded to go along and nail Kirby with some hard questions about the facts, as opposed to his conspiracy theories and scaremongering. If you would like to give your MP a prod, you can contact them via, or look up the email address of any Lords you can think of with medical or scientific know-how here.

I have little doubt that anti-vaccine types are writing to their MPs as you read this, urging them to give an ear to Kirby’s anti-vaccine PR. So feel free to give your elected and non-elected representatives a more scientific steer.

Stop press: Mike Stanton has just added a second post about Lord Hodgson’s comments on thimerosal and vaccination. Mike’s take is that Hodgson should be careful who he takes scientific advice from, as someone has been pointing him to some dire “anti-vaccine fringe science”, including a couple of notoriously awful papers – read the post for more. The dangers of self-styled experts and cargo-cult science are, of course, topics familiar to readers here.

Follow-up: To hear an eye-witness account of what a damp squib it turned out to be (i.e. no-one at the lecture but the usual mercury /vaccines conspiracy crazies, and barely anyone at all at the House of Lords), click here and follow the links.


The Vote is in

May 21, 2008

– as of three hours ago.

And, for now, the liberal social consensus just about continues to hold in the UK.

The amendment (to the Embryo Bill) to reduce the abortion time limit to 20 weeks (a time point heavily promoted by Nadine Dorries MP, of the “Twenty week campaign”, and sundry other crypto-antiabortionists) was defeated by 323 votes to 190.

The crunch amendment on reducing the limit by two weeks to 22 weeks was defeated by 304 to 233.

Other amendments, designed to embarrass Gloomy Gordon and to make symbolic points about what kinds of families should or should not be allowed to have children via IVF, were also defeated by similar margins.

And all live on TV. The BBC parliament channel is not exactly the most entertaining television. But somehow tonight seeing it live seemed to be important.

Not so much because I have an overwhelming interest in the issue of abortion, I should say. Abortion, and the science and culture wars that surround it, is not something I tend to think about unless my sole Evangelical Christian scientist friend tries to start a moral discussion about it.

What has concentrated my mind, and that of many other UK science bloggers, is the way that the anti-abortion side in particular misused the scientific and medical evidence to promote their view that the limit should be lowered “because the facts say so”.

The scientific and medical consensus on the Bill (for), and on the figures for fetal viability (no convincing evidence that the poor survival pre-24 wks has changed), has been near universal. But this has not always been clear in the press coverage.

There are a number of stories that could be written about the Embryo Bill, the abortion time limit, and the coverage of both.

One might be about “The four miracle babies”. These are four 22 week gestation infants, born at University College Hospital and treated in their Neonatal ICU over a period of five years, whose survival Nadine Dorries MP apparently feels outweigh pretty much all the other medical evidence about the viability of very premature babies in the UK.

A further topic might be the things different religious groups believe about the onset of life in utero – interestingly, these views are not as fixed as you might think – and how their views map (or don’t) to the foetal embryology.

And still another, or possibly an extension of the last topic mentioned, might detail “some things the pro-life lobby don’t tell you” about fertilization and early pregnancy.

No promises, and foetal embryology is definitely not my scientific field, but I may try and tackle one or two of these if I have time.

But to close this little recap, I have reproduced below the key summary diagram from the Trent study published last week in the BMJ. This study, more than any other piece of evidence, probably ensured that MPs voted to retain the present 24-week limit. The diagram shows survival to discharge from hospital of very premature babies born in the Trent region and admitted to the neonatal ICUs . The take-home message was that, while advances in therapy had improved survival for infants born at 24 weeks or later, before 24 weeks the picture had not changed, and remained grim. Worth a thousand words.


May 19, 2008

As I sit here, the first day’s votes on the Human Embryo Bill currently before the UK parliament have happened, with the creation of hybrid embryos approved by a large majority.

A lot of scientists will have sighed with relief. However, to most scientists, the whole furore over hybrid embryos was a puzzle. Why such a fuss when “100% human” embryo research was already legal?

I have not written anything about the Bill hitherto. Partly, this is because it is a huge subject. Where to start? Where to stop? It has certainly been misreported. Even the people you would expect to report it accurately have been falling down.

For instance, as I was sitting here writing yesterday evening, the usually reliable Radio 4 told me that:

“Scientists want to harvest stem cells from these (hybrid) embryos to treat diseases such as Parkinson’s disease and Alzheimer’s”

Aaargh! Why can’t these people get it right?

Every time this lazy line was repeated over the last few weeks more confusion was propagated across the airwaves.

The line should actually read:

“Scientists want to harvest stem cells from these (hybrid) embryos to work out better ways to treat diseases such as Parkinson’s disease and Alzheimer’s”

– which is shorthand for:

Scientists want to harvest stem cells from these (hybrid) embryos to work out better ways to treat diseases such as Parkinson’s disease and Alzheimer’s.

– The hybrid cells will allow the methods to be worked out in animal experiments but without having to use real human embryos to provide the stem cells. That way we will see sooner if stem cell therapy is practical, and under what circumstances, without needing to destroy lots of human embryos.”

The crucial distinction regarding what is actually going to be done with these hybrid embryos should have been in every story concerning the vote. But it has not been.

Scientists prefer data – Pro-Lifers prefer dogma

This has suited one group of people very well. This is the array of religious and “Pro-Life” groups opposing the Bill.

A central theme of the religious objections has been that the scientists are “doing something monstrous” in trying to create “human-animal hybrids”, that the scientists are “tampering with the very nature of life” or “tampering with the very nature of what makes us human”.

Note the term “human-animal hybrid”

A more accurate description would be “human animal hybrid ball of cells

The idea – which the Churches and Pro-Lifers have happily stirred up fear of – of some mad boffin taking the Bill as a green light to create a human with mutant hamster genes is utter science fiction.

In fact, what MPs have just voted for was only marginally different from what already occurred under the previously existing law.

So what was legal already?

To recap: under earlier British legislation, passed by John Major’s Conservative government in 1990, unused human embryos generated during IVF could be grown until they are 14 days old. They could also be used to make embryonic stem (ES) cells.

The crucial decision, then, to allow “leftover” human embryos to be used for research, though only under limited and legally-restricted conditions, was taken by parliament 17 years ago.

Looking back over those 17 years, the sky has not fallen in. Human clones are not among us, so I cannot pay to grow a replica Dr Aust in a tank to use for replacement parts.

Two weeks only

A word about the “14-day limit”. This time point was set as being the time when the very first signs appear in the ball of cells (called a “blastocyst”) of the structure (called the “primitive streak”) that will ultimately become the central nervous system.

The same rules apply to the hybrid embryos, as noted in the recent House of Commons debate on the 2nd reading of the bill by Conservative MP John Bercow:

“Is it not worth underlining that [hybrid] embryos will be subject to the same regulatory procedure that applies to embryos at present, namely the requirement for destruction at 14 days, or upon the emergence of the primitive streak? Therefore, the idea conjured up by some of the more lurid speculation in the tabloids that there will be some persistent ongoing consequence is nonsense.”

So why all the fuss?

The reason scientists have been so mystified by the denunciations of the current Bill from religious groups is that the hybrid embryo experiments were thought up precisely BECAUSE of the ethical objections religious groups continue to raise to the (legal) use of real human embryos created by IVF. The Pro-Life groups insistently refer to these embryos as “human lives”. Reasoning that there was no intrinsic need to use genuine human embryos for much of the research and proof-of-principle work, the scientists had a think and came up with a reasoned alternative – an animal egg loaded with “re-programmed” DNA from an adult human cell. The total amount of “animal” DNA in such a hybrid embryo is 37 out of 30-35,000 genes. This is because the only animal DNA comes from the egg’s mitochondria, which contribute 37 genes in all. The “0.1% animal”, or “99.9% human” figure, comes from this 37 out of 30-odd thousand figure.

So- you’d think the Pro-Lifers would have been happy. Far less need for human embryos. But no – instead, all we got was months of craziness about “Frankenstein hybrids” and “tampering with nature”.

The central fact that anything other than growing-a-ball-of-cells for 14 days-in-a-dish will still be ILLEGAL under the new law, just like under the old law, has not always been clear in much of the media coverage. It is pretty clear to me that the religious groups have done their best to obfuscate this deliberately, and that too much of the media coverage, especially early on, allowed them to get away with it.

Barking mad

To give a particularly emotive and mad example, back in January John Smeaton, national director of the Society for the Protection of Unborn Children, spoke as follows:

“The decision [to allow creation of a hybrid embryo] represents a disastrous setback for human dignity in Britain

It is creating a category of beings regarded as sub-human who can be used as raw material to benefit other members of the human family, effectively creating a new class of slaves.”

Now personally I cannot work out how a 14-day ball of cells with no hint of a nervous system, or a stem cell derived from it, is anything like a “slave being”.

Obviously I do not live on the same planet as Mr Smeaton.

Contrast the statement by John Bercow MP. He, though he is not from the party I vote for, clearly inhabits a planet I recognize. Indeed, one of the interesting aspects of a read through the Parliamentary debate on the second reading of the Bill was the way the debate transcended the political party affiliations of the MPs speaking.

Catholic and Evangelical Christian MPs opposed to it, root and branch. Everyone else pretty much for it, though to varying degrees.

Also for the bill, though outside parliament, were and are the scientists, including sundry Nobel Laureates and the Royal Society. And also for it are the patients with incurable diseases who might ultimately be helped, together with their families. And also for it are all the medical charities that do research into disease and cures, like the British Heart Foundation, the Wellcome Trust, the Parkinson’s Disease Society etc. etc.

Oddly, the voices of these folk were heard rather less in the media, at least until the last couple of weeks, than the strident tones of the objectors spouting their soundbite inaccuracies. Initially –at least as I see it – far too much of the media coverage of the Bill, and of hybrid embryos, simply reported the doomsday utterances of Smeaton and other factually-challenged commentators like Nadine Dorries MP.

And the coverage…?

As time has gone on, the media coverage has become more accurate, though not accurate enough for my liking, see the start of this post. And the national media have not been paragons of accuracy. Indeed, some of the most succinct statements of the facts I found were in the Parliamentary debate last week, which is not often the case. It almost restored my sometimes wavering belief in the idea that the people in the House of Commons are really doing, and capable of doing, the job they are elected for.

There were some media stand-outs. The Guardian’s James Randerson has covered the issue well. And reality has poked its head up even in unexpected places, especially as the vote has neared. For instance, here is the Sheffield Star, managing to make the key point succinctly in a way that has mysteriously eluded many of London’s Finest Journalists.

”The Bill permits the creation of embryos containing human and animal material for studying diseases like Parkinson’s and Alzheimer’s. The legislation would allow scientists to grow the embryos for up to 14 days.”

Note: 14 days. Grow.

Not: “Turn them into a hybrid being with mutant DNA and animal powers”.

“Slave sub-humans” – do they really believe this stuff?

Now, I find it difficult to believe even the more frothing Pro-Life groups could not tell the difference between “ball of cells for 14 days in a dish” and “slave sub-humans”.

So why have they been shouting so loudly about “scientists opening Pandora’s box?” and “invading the sanctity of human life”?

The answer, quite clearly, is that they saw an opportunity to re-fight the battles they lost in 1990, when the original Embryo bill was passed, and in other battles over things like abortion and cloning.

But… we’ve been here before

One of the more ironic aspects of all this, to my mind, has been the spectacle of the Catholic, Evangelical and Pro-Life lobbies casting themselves as “victims” and complaining that religious views are “marginalized” in contemporary Britain.


For those that weren’t around back then, the 1990 Embryology Bill was, of course, passed only after an extended debate, both in Parliament and outside, in which the religious groups had a substantial voice. Their views on “the nature of human uniqueness”, and of “the point at which a human being is created”, and “when is a human soul created” all fed into the argument, and indeed led in large part to the compromise choice of the 14-day limit on embryo research. The point was that one could hardly talk of a “human consciousness” or “a human soul” being destroyed if the 14-day blastocyst did not even have the beginnings of a nervous system.

All the new law has done is to say that a hybrid embryo gets the same protection as a human embryo. As MP and doctor Evan Harris put it in the second reading debate:

“The reason why the Select Committee advocated including true hybrid [embryos] in the [legislative regime controlled by the] HFEA [that could] license their use if an appropriate application came forward was that there was no good reason not to. Once one accepts that it is legitimate to do destructive medical research on human embryos, there is no ethical reason to give greater protection to things that are not human embryos. It would be an inversion of everyone’s ethical compass to say that certain embryo entities require greater protection than a fully human embryo.”

Of course, consensus politics, and a search for compromise, does not please everyone. People whose religion “calls” them to an unchanging moral viewpoint will never give up trying to roll back the democratic consensus if that consensus – whether on legal abortion at 24 weeks, or on hybrid embryos – conflicts with their moral code. And they are very committed, and very vocal.

An inbuilt property – some might call it a snag – of democratic processes based on discussion is that the very vocal minority sometimes appear, by their very vocal-ness, to be more numerous than less-vocal majorities.

Which, some scientists would say, is why we need lobbyists, eminent scientists speaking out publically, Emails to MPs – I’ve sent mine – and demonstrations, and possibly even a blog or two.

And hopefully, elected representatives who can spot a silly argument. Tonight it looks like we may do. But tomorrow is another day.

Experts: hired lackeys – & moon made of cream cheese.

May 8, 2008

It is a bit of a tough gig being an “expert” these days.

Not so much in what I do, of course. It is not as if there is all that much controversy – or interest – surrounding the Delta-like cells of the crayfish hepato-pancreas, or whatever it is people like me spend their time fiddling about with. Even if I were to put on my work website that I was a “world-renowned expert in cell physiology”, or whatever, it would raise few hackles, although the thirty people worldwide that actually read my papers would have a quiet snigger at my delusions of grandeur.

The wider world, I predict, would be unconcerned.

– until I start commenting about alternative medicine, or CoQ10, or homeopathy, at which point I will get accused by people I have never met of being in the pay of “Big Pharma”, or, as our nearly four yr old, Junior Aust, says, ”Evil Farmer”.

For the record, the biggest “payday” I have ever had from Big Pharma was a free lunch (once) in AstraZeneca’s nice staff cafeteria at Alderley Park. Other than that, nothing – not even a small consultancy fee. *sigh*

But it is quite different for experts in things like medicine… the stakes are high, and some people nowadays seem to think that all “Experts” are corrupt tools of Shady Corporate Interests, or of “the Medical Establishment”.

So what really makes “an expert”?

It is a truism of science that the more you know about something, the more “expert” you are. For this reason, the average person who reviews scientific papers for a serious scientific journal – an “expert reviewer” – will be someone who has a degree, a PhD, several years’ worth of postdoctoral research experience, and preferably does, has done, and often supervises other people doing, work very similar to the stuff they are reviewing.

The point is that you have to know the subject, and the type of work, and how it is done, inside-out to see the errors, if any. And also to see where the authors may have finessed things slightly by comparing things that are not strictly comparable, and so on.

The result is “expert peer review” – a fully-informed expert opinion on a particular piece of research, or on the latest meta-analysis.

You know you are an expert in this sense because other experts decide that you are. For instance, proper high-end science journals (and this does not mean all the thousands of journals you can find listed on Pubmed) are picky about their expert reviewers, as it is on these peoples’ rigor that a journal’s standards depend. It is for this reason that scientists sometimes list, on their professional CVs, the journals they review work for.

Conversely, I think we can say it a safe bet that the venerable Journal of Physiology is not going to be asking Sir Cliff Richard to review the next paper about whether antioxidants help older athletes get less post-exercise muscle pain.

Sir Cliff is not, whatever the food supplement industry appear to think, an expert.

However, not all public statements about research, especially medical research, or its interpretation, come from the experts.

Indeed, on many issues expert opinion is vastly outweighed by comments from what one might politely call “advocacy groups”. These include, but are not limited to, patient groups.

This presents interesting problems. One in particular is: can one trust the messages emerging from such groups?

And if we say no, are we saying that only real experts should be allowed to have a view?

Context is critical (again)

Well, let’s stay with the profile of an expert, and their ability to interpret the evidence. This ability to interpret research is a question of degrees of relevant knowledge. But it also depends critically on being able to put the research in the proper context – that is, having the background to know things relevant to the research that are not explicitly written down in the paper.

This is something scientists, and doctors, are taught in varying ways. But they are taught it. For instance, take a PhD viva (the oral examination that follows the submission of a PhD Thesis and constitutes – hopefully – the last stage of getting a doctorate).

In the viva, you do not get asked about just the experiments in your PhD thesis.

You also get asked about other experiments in the literature that bear on whatever question or questions you are seeking to answer. You get asked about the broader background area, and where your work fits it. You get asked about the key theories in the area that underpin and lead up to your work, and how strongly the experimental evidence supports them. And you get asked why Dr Y’s experiment got a different answer to yours, particularly in terms of analyzing the differences between your experimental design and Dr Y’s. Was the answer different because the patient blood samples in your experiments came from women aged 16-20 who volunteered for a specific study, while Dr Y’s were from women aged 18-30 who had been sampled for a study into something else? What are the potential ways that that could make your study populations different and thereby explain the different answers you got? Is there other evidence to support any of these potential explanations?

…and so on, and so on.

And apart from being taught it, this “contextual knowledge” is also acquired bit-by-bit over years in research, or medicine. It forms one useful kind of accumulated experience.

The reason I am harping on about this is that many advocacy groups include, or even employ, people who have read a lot of medical and scientific studies, and sometimes consider themselves experts. But their expertise often lacks a critical dimension: they commonly do not understand all the background. And I mean “background” here in a very broad way; I am including not only “the broader science in this field” and “earlier studies like this”, but also “the underlying assumptions of the work”, “the ways in which studies like this can be biased” and – very critically – “the ways in which statistics and statistical testing work in relation to this kind of experiment”

From the above, you can see that there are a lot of different levels of understanding that one can have in relation to a scientific topic.

Which is NOT to say that you cannot have an opinion unless you are a full-on “academic ninja” expert. I mean rather that you should try to recognize the limits of your knowledge, and understand that other people will inevitably know more (or less) about it than you.

[This goes, incidentally, for doctors and scientists, obviously including me. I know more than some people, and less than others, and this is subject-dependent. I know, for instance, more about acid-base balance than most physiologists. But I know less than a hospital doctor, who in turn knows less than a real “acid-base ninja”, like an anaesthetist or intensive care specialist]

Of course, in the public arena, many or even most people seem to not be too good at this “grading” of their level of knowledge.

To take an example…

As an illustration, take the controversy over home birth. Dr Crippen over at NHS Blog Doctor is currently taking a shot at some midwives in Kent (these midwives are independent of the NHS and charge for their services). They ran a home delivery for a mother with a long string of “risk factors” that would have lead any obstetrician, and probably most NHS midwives, to conclude that the mother would have to be bonkers to want a home birth. Dr Crippen is angry because the independent midwives seem to be unaware of the dangers, continually referring to the caution of the mainstream doctors and midwives as “shroud waving”.

The case described by Dr C is pretty extreme, judging by what my medical advisor (Mrs Dr Aust) tells me. But home birth is a contentious issue all around.

And in homebirth, a battle is being fought over precisely what the statistics tell you about whether home birth is more dangerous than giving birth in hospital, and by how much.

The doctors I have asked are unanimous; home birth is more risky for both mother and baby, they say, mainly for the obvious reason that if something does go seriously pear-shaped, you want to be in a hospital.

This extra risk, the doctors concede, may be slight and acceptable for ultra-low-risk normal births under ideal conditions, that is, where the overall (absolute) risk of something going pear-shaped is very small. However, the more “non low-risk” the pregnancy (i.e. the more factors there are suggesting an increased chance of complications) the relatively riskier home birth becomes. And if conditions are not “ideal” (for instance less experienced midwife, long drive from nearest maternity hospital in case of pear-shaped-ness, etc), then that all adds to the risk that is being taken.

For what it’s worth, among all the female doctors with children Mrs Dr Aust and I know, we have never met a single one, in any specialty, who opted for a home delivery.

But the home birth groups dispute the above view, and also the idea that the doctors, and even the hospital midwives, are speaking from expertise rather than ”medical paternalism”. The home-birthers feel they should have the right to choose home birth. They also point to published analyses that say that for low-risk deliveries, home birth is no more dangerous than hospital birth. Typically, a fierce and detailed argument then ensues about exact which figures do (or don’t) mean what different people say they mean. If you want to see this in action, try the discussion thread following Dr Crippen’s post

So – who to believe?

I won’t give my own opinion, for the following reason: I am not an expert in the relevant areas.

However, I think I can say who I would regard as “an expert” on the question.

It is, as ever, a question of “degrees of expert knowledge”. Who are the people most likely to know all the studies, all the background, all the factors influencing the trustworthiness or otherwise of individual studies, and all the hidden catches in comparing different patient groups and studies?

Well, for me, it’s no contest – the answer is that I would put Professors of Obstetrics & Gynaecology (O&G), or experienced hospital O&G consultants, at the top of the expert scale for this particular issue, and Joe and Joanna Public at the bottom.

The advocacy group people, even if they have scientific or medical backgrounds, would rate well below the Professors and consultants, at least for me. This is both because they have a clear agenda going in, and also because they mostly lack the full background necessary to interpret the evidence properly. I would thus be suspicious about whether any message they were putting out was strictly accurate. And my personal bete noire, journalists with no training in science or statistics, would rate pretty damn low on the expert scale, though we hear a lot from them on this issue (for a particularly misleading recent article see last week’s Guardian here).

Personally I think there is a lot of danger in folk who cannot see that there are people who know more than them (or even concede that such people probably exist) when looking at this and other issues to do with interpreting research. To repeat it again, you have to be aware of how much you know, and how much you don’t, if that doesn’t sound too Donald Rumsfeld.

Where to find the good stuff…

Plus, once you have established you don’t know enough, you also have to know where to get the information that you are missing, and from whom.

To give one example: let’s take a family doctor who has heard something about all the homebirth discussion, but hasn’t read all the recent studies, and is confronted by someone who insists that they have read that the statistics say home births are as safe as hospital births.

The doctor knows he or she needs reliable information. Luckily they know that, say, a Cochrane review written by an O&G Professor would be the place to go for the goods. And they would almost certainly rate this higher in their “evidence hierarchy” than a review in a lesser scientific journal penned by the chief advisor of a charity that promotes home births. They would certainly rate published journals studies higher than figures quoted on websites that have never been through peer review.

That is not all there is to it, of course. Our hypothetical doctor might read the two reviews side-by-side, comparing what they said about individual studies, and thus improving their understanding of how research in the area is interpreted.

Where to put your trust?

Now, this is fine if you have relevant expertise and know what to do, and where to go for information.

But: how does this discussion about the nature of experts help Joe Public when he or she is confronted by the need to make a decision? Or in the case of prospective parents and the home birth issue specifically, who should they get their messages from?

As I see it this reduces to – who can you trust to have an expert view on this, and communicate it to you without a hidden agenda, whether ideological or financial?

My answer for childbirth, having been through it as a prospective parent, would be the obstetricians and hospital midwives. Because it is their business to know the facts, and also their professional responsibility to try and get the best outcome for you and your unborn child.

In contrast, I would not expect to get anything like a dispassionate view from a homebirth advocacy group, even when they say they are “quoting the studies”.

The trouble is that there is so much propaganda about, much of it masquerading as journalism – see e.g. the Guardian article linked to above – that it must be incredibly difficult for people to know who to believe.

The danger is that they will make the decision first, based on irrational fears or on preconceptions that may be mistaken. And they will then get this uninformed decision reinforced because there will be some information, somewhere, that agrees with and applauds their choice, even if their choice is objectively ill-advised.

To me this parallels other “reality meets preconceptions” problems in health like the MMR vaccine saga. Once people have bought into the idea that “the doctors / experts / government aren’t telling me everything” – or that the doctors are pushing a particular agenda , “medicalising birth” or “pushing drugs and vaccines for Big Pharma” – then the patients / parents are cast adrift amid a sea of misinformation. They – or perhaps I should say we, since I am a patient too – are at the mercy of lots of advocacy agendas, all too commonly armed with prejudice, misguided certainty, and masses of misused stats.

Experts under fire

So just how did we end up doing this to professionals and experts? Have we, as a society, decided that their opinions are just another optional paid-for add-on?

Experts and professionals certainly are sometimes mistaken. They sometimes do not explain enough. They certainly do not get enough help from professional explainers explaining science and medicine. They are, rather too often for my taste, hung out to dry by Governments who pick them up and dump them as a matter of political expediency. And finally, experts are at times guilty of digging their own holes to fall into – e.g. by doctors trousering large consultancy fees from pharmaceutical companies.

But is that enough to dump expert views entirely? Do we really think all mainstream experts are incompetent and arrogant? Or that self-interest is their only motivation?

Personally I am happy to let the pilots fly me, the anaesthetist anaesthetise me, and the lawyer tell me what is, or isn’t, legal. And I am also aware that you can’t believe everything you read – though on the whole I believe it more if the writer is a real expert, and is not trying to sell me something.

But it sometimes seems, these days, that I am in a minority on both counts.

It is a worry.

PS Sorry for the long and boringly unfunny ramble. Hopefully there will be more satirical snarking next time.

Quote of the day: “I can live with doubt and uncertainty and not knowing. I have approximate answers and possible beliefs and different degrees of certainty about different things… It doesn’t frighten me.” – Richard Feynman