Regular readers of this site will know I tend to give my blog posts quite literal and descriptive titles: Why is the dietary advice given to diabetics so often so woefully inadequate?�, that sort of thing. So, I promised to write about sunlight and beta-carotene today (which I will, give me a moment�), but thought I’d use a less obvious title today because it might just lure the attention of the individuals who have taken great issue with the fact that I believe that the evidence used to vindicate MMR with respect to autism is ‘shoddy’ (and don’t mind saying so). The evidence does no such thing. Not even close. And seeing as this is a matter of extreme importance in terms of people’s lives, those who maintain that the evidence proves that MMR is safe with regard to autism I believe are misleading the public in a way which may be having grave consequences. Let’s hope not, but we just don’t know.
The scientific evidence these people cite is like a two-legged stool: every time they put it up, it falls down again. If you’ve been following the ‘debate’ unfold over the last few days you may now be of the view that the only thing to admire those who keep attempting to put the stool up again is their persistence.
But, it’s a pointless, exercise, I reckon, and these individuals need putting out of their misery. And the fact remains that we need more evidence to know beyond reasonable doubt that MMR is not responsible for a whole different sort of misery, in the form of regressive autism and the lives it can blight.
So, the title above is partly a reference to the whining that’s been coming from a group of individuals who know the game’s up, but still proclaim MMR’s innocence.
But the title is also a reference to what this blog is really about, which is about beta-carotene, and its ability to help prevent sunburn (geddit?).
Those that read my blog on Monday may remember that I was due to write about this subject then, but the weekend had been grey and drizzly, and I was diverted by the MMR/autism thing anyway. Now, right on cue (where I am anyway), the sun is out, and it therefore seems like an ideal time to deliver on my promise from Monday.
Beta-carotene (the nutrient that is responsible for the orange colour of carrots) comes from a family of nutrients known as the carotenoids (I wonder why). Beta-carotene has what is known as antioxidant action, which means it helps neutralise damaging, destructive molecules known as free radicals. Now, free radicals have a role to play in sunburn (sunlight exposure increases free radical production in the skin). So, in theory at least, more beta-carotene in the body and specifically the skin may help prevent sunburn.
Several studies have looked at whether beta-carotene does do this in the real world, and the study I’m focusing on today took 7 such studies, and lumped them all together in the form of what is known as a ‘meta-analysis’. In the individual studies, beat-carotene dosing ranged from 15 ” 180 mg per day. The conclusion of the study was that beta-carotene did indeed have the capacity to offer protection against sunburn. This study also looked at how long individuals need to take beta-carotene for before their skin is ‘primed’. A minimum of 10 weeks is the answer. So, sorry, if you live in the UK and haven’t been dosing up on beta-carotene then you’ve missed the boat rather. On the plus side, there is always next year.
Beta-carotene is not the only nutrient that might help prevent sunburn. See here for a recent blog which looks at this, as well as giving an account of the nutrients which may actually promote tanning.
References:
1. Kopcke W, et al. Protection from sunburn with beta-carotene ” A meta-analysis. Photochemistry and Photobiology. 2008;82(2):284-288
The MMR nonsense really isn’t “a matter of extreme importance in terms of people’s lives”. If there is a risk of autism, which there almost certainly isn’t (and frankly the phrase “almost certainly” doesn’t do justice to the staggeringly tiny likelihood that there is such a risk), then it’s small enough to be totally irrelevant when compared to the risk of being actually killed to death by one of the three far more common and potentially fatal diseases against which the jab provides very effective protection. Whether or not the risk exists doesn’t matter at all: the vaccination is a very, very good idea in either case.
In what way is it of even the remotest importance?
are you saying that you agree with the findings of the meta-analysis or are you not sure?
I find it interesting that Dr Briffa fails to note the authors’ point, made in the full paper, that:
As well as their note about use of strategies to reduce beta-carotene dosage, because:
Anthony
When I wrote “…but [I} thought I’d use a less obvious title today because it might just lure the attention of the individuals who have taken great issue with the fact that I believe that the evidence used to vindicate MMR with respect to autism is ‘shoddy’ (and don’t mind saying so).”, I meant it: I was hoping that someone might take the bait and come here in an attempt to score some easy points, perhaps as comfort after having the knocking stuffed out of them elsewhere.
Deep down, I did not really expect someone to fall for it, let alone you. But it seems I overestimated you, Anthony.
Word of advice, Anthony: don’t take up poker and if you have already get out quick! Think of the mortgage!
Andrew
The relevant scientific work has not been done to assess properly what (if any) risk of autism there is associated with MMR vaccination. So, what you appear to have done is confidently predict the results of an experiment ahead of time. How ‘scientific’ do you regard this to be, exactly?
It appears you have developed some magical clairvoyant powers which is fine by me, but some may see as a bit ‘woo’, to be frank.
You are seriously asking me to believe that your views on the beta-carotene paper were carefully written in order to sucker me into making criticisms of your lightweight reporting of the paper concerned?
This seems a rather unlikely, if convenient, post-hoc idea, given the standard of postings about other nutritional issues on your site.
Anthony
“You are seriously asking me to believe that your views on the beta-carotene paper were carefully written in order to sucker me into making criticisms of your lightweight reporting of the paper concerned?”
I don’t care what you believe: in this instance it’s what other people believe that counts. Don’t you get it?
You call my reporting ‘lightweight’. On what basis? Because you went to the article and pulled from it things that I hadn’t quoted? Forgive me, but this does seem a most desperate attempt to score some sort of hit. And you know I’m right, don’t you?
You promised to never post on this site before, but it seems you just can’t stay away. More than once you’ve ended up having to drag yourself off the canvas. I think we know who the real ‘lightweight’ is here.
so, um, is it your opinion that Beta-carotene might help prevent sunburn?
Heh. I’m, as guilty of rubbernecking car crashes as the next guy.
I am very pale skinned so this could be useful to me. I used to smoke til last year. Is it still ok for me to have the carotene?
Hi
Sorry – posted a comment here earlier on but can’t see it now. I gave up smoking last year. Is it still safe for me to have beta carotene supplements as I am very fair skinned and I thought it might help.
Andrew
Please cite evidence for this pomposity:
“The MMR nonsense really isn’t “a matter of extreme importance in terms of people’s lives”. If there is a risk of autism, which there almost certainly isn’t (and frankly the phrase “almost certainly” doesn’t do justice to the staggeringly tiny likelihood that there is such a risk), then it’s small enough to be totally irrelevant when compared to the risk of being actually killed to death by one of the three far more common and potentially fatal diseases against which the jab provides very effective protection. Whether or not the risk exists doesn’t matter at all: the vaccination is a very, very good idea in either case.”
Jonathan
I’m afraid I don’t answer personal health queries on the site.
Anthony
And still he comes back for more! I’m wondering if you’re developing a bit of a taste ritual humiliation in public, Anthony Cox.
So that we’re straight on the events so far:
1. I claim the evidence used to vindicate MMR with respect to autism is ‘shoddy’.
2. You claim it is not.
3. I ask you to provide the evidence to support your stance.
4. After repeated requests, you finally cough up the science and promise never to post again on this site.
5. I reveal the science you provide to be utterly inadequate from a scientific perspective.
6. Despite having promised never to post on this site, you return, this time in an attempt to claim I believe that MMR causes autism.
7. I put you straight (again), and again you find you are unable to ‘score points’.
8. Having had your fingers burned twice, you decide that MMR and autism is an area in which you clearly can’t win, and move to criticising other things I’ve written, which have nothing to do with the debate at hand.
9. I reveal you’ve been ‘had’ (again).
So, when you say you enjoy rubbernecking, I suppose the obvious question is: ‘Does this include when it’s YOU who is the victim of the tragedy?’ It seems so.
Maybe you do have some masochistic tendencies after all.
Dr B I think you are completely correct in your opinion that the link between autism and MMR has not been properly investigated.
I think you are also completely correct to point out that all the evidence used to supposedly demonstrate that MMR is safe is epidemiological in nature and thus is simply not able to disprove a causal link.
My problem is I don’t know what different approach you are advocating?
Are you suggesting a large scale intervention study? Could you suggest a design. I am not a researcher but I am not sure how ethically, this could be done.
I do mean this as a genuine question
Dr Briffa,
I have not “confidently [predicted] the results of an experiment ahead of time” (which seems to be one of your favourite nonsense accusations of late). We already have a huge experiment: the MMR vaccination is routinely used in most major population centres in the western world and I don’t know anyone who is autistic. If there was a risk of autism above 0.2% or so then I would expect to know, at least in passing, at least one person who was autistic because of this intervention. That has not happened — what really are the odds that all those people just got lucky? Furthermore, if the risk existed and was large then it would almost certainly have shown up in credible studies by now. It hasn’t. If there is a risk, which is preposterously unlikely, then that risk is tiny. Those are the facts and I can’t fathom why you would deny them, except perhaps if you are now so deeply embroiled in this nonsense that you feel you can’t get out gracefully.
Well, you can. And you’ll be more respected for it — at least in the scientific world. The people who buy your books might think differently. But I’m not going to stoop to your level and accuse you of lacking integrity just yet. Hanlon’s razor and all that.
Andrew
Andrew
“I have not “confidently [predicted] the results of an experiment ahead of time” (which seems to be one of your favourite nonsense accusations of late).”
It’s not nonsense: it’s an accurate description of people who makes assumptions before relevant research has been done and the facts are in.
“Furthermore, if the risk existed and was large then it would almost certainly have shown up in credible studies by now.”
What ‘credible’ studies? Do cite them (if you can).
But one thing I suspect you will understand is that as this debate goes on, people will get more suspicious about MMR’s safety with respect to autism, not less. Why? Because you and others like you have drawn attention time and again to the fact that the current evidence does not vindicate MMR with respect to autism.
I suppose we have something to thank you for.
It is also the good fortune of many autistic people that they do not know Andrew. On the other hand Andrew seems to have overlooked the fact that autistic people, most of whom are still under 20 years of age, have impaired social competence, and so are unlikely to meet important people like him, unless it is part of his job – which seems unlikely.
http://homepage.ntlworld.com/clifford.g.miller/pandemic.htm#Scottish_Autism_Audit_Cannot_Find_Enough
This is indeed a very odd way to conduct science – it looks like Andrew might have some tricks even to teach such luminaries in the field Sir Michael Rutter, Elizabeth Miller, Brent Taylor and Eric Fombonne about epidemiological method.
I can’t help but point out that autism is far more prevalent than Andrew assumes and, like John, I’m glad Andrew doesn’t know anyone autistic. The chances of getting autism are small, but if you are in that 1% or 2% it’s a big deal. Andrew, perhaps please read up before you comment?
Setting aside a cheap shot about you predicting what will happen before anyone does the experiment, I would suggest that that’s because there is absolutely no reason for anyone to think there is a risk other than the presence of debate. The fact that your side of the debate is populated entirely by people with obvious vested interests and the ill-informed will reassure most observers but some people are not that canny. You can manufacture doubt about anything you want if you’re sufficiently persistent. It proves less than nothing.
There are loads. There were some in the Cochrane report. None of them perfect but good enough to be credible. If there was a large risk they’d have found it. The fact that they didn’t suggests that the risk is either small or absent. But I’m not going to waste my time looking up, reading, and citing specific ones because I know that you will simply (a) look for any flaw you can and implicitly declare them worthless, (b) cry that they don’t prove the vaccine is safe, even though all I claim is that they don’t show it isn’t and (c) point out some arcane study that shows the opposite, probably in hippos or chaffinches or something equally irrelevant.
Why do you think I have no compassion simply because I disagree that there is a significant possibility that the disease is caused by vaccination? I’m not going to pretend someone is right because they might get upset. I’ll be tactful when I need to be, right now I feel I need to be forthright.
Well, if it was part of my job (which should seem unlikely given that I said I don’t know any — I’m not that crap at my job) then that would be an equally bad sample in the other direction.
You’re right, of course, I had overlooked that, and that was wrong of me, but it doesn’t change the facts: my experience is roughly what I’d expect from prevalence stats without that effect. Vaccination is at something like 90% and autism is at something like 0.7% — being generous and including all the really nothingy borderline ASD cases. For stricter measures, that number drops as low as 0.04%. Even if every single case of autism in the country is the direct result of vaccination, we’re still looking at a risk between 0.8% and 0.045%. Let’s remember also that you have a 90% chance of catching measles if you live with someone infected and a 0.1% chance of dying if you do. Probably it would be more than that if there was an epidemic caused by low immunity rates — the hospitals would be all full at once, which would lower the quality of treatment, and there’s a chance it might develop resistance to the treatments.
If there’s a risk then it’s tiny. Are you honestly going to disagree with that? If you’re not then stop demanding evidence — or do you just do that as a matter of policy whenever anyone says anything inconvenient?
(Besides which, I knew a good hundred of these people at school, when we all got the jab. None of us suddenly became autistic and had to be taken away. I’d remember that. Unscientific it may be, but this was a prospective ad-hoc, uncontrolled trial. Oh, yes.)
Em
I reckon the reason Andrew doesn’t know anyone with autism is because he’s a solitary soul. Have a look here http://www.apathysketchpad.com/blog/about-me/ and you can see it appears he’s even had to take his photograph himself. Bless.
Hi Dr Briffa
On reading your article again I guess you must agree that it is likely that beta-carotene supplementation reduces the risk of sunburn, at least based on the meta analyis you cited?
I don’t think it’s the case that ‘you don’t know’ because you haven’t explicitly stated that lilke you did in the MMR pieces.
thx
Bloody hell you’re pathetic, Briffa. Is this the level you argue on? You trawl people’s blogs looking for any feeble pretence to insult or discredit them on?
Honestly, I used to think you were just wrong, that you’d just missed a subtle concept about the nature of proof, but I’ve lost all respect for you now. There’s no point engaging with someone who thinks that “haha you have no friends lol” is a passable response to a critic.
I’ll happily debate this topic with you further, but only when you learn to converse like an adult.
Em,
For the record, I did read up. Not thoroughly, mind — it’s only a blog comment. But the National Autistic Society who ought to know say it’s less than 1% so I don’t think my quick-Google-number of 0.7% understated it much.
Why are you glad I don’t know any autistic people? You, Stone and Briffa all seem to have assumed that I’m this disagreeable all the time. I’m embroiled in an argument with a guy who thinks “he must be wrong because i imagine he has no friends” is an argument and you expect me to be compassionate to people who aren’t here.
Yeah, you’re scoring huge empathy points there.
Andrew
And at last I feel we’re starting to get somewhere with you. Because it seems to me you are starting to feel just a little of what the parents (who believe their child may have autism as a result of MMR) might feel when you ‘belittle’ them (your word, not mine).
Perhaps you’d like to reflect on this again, if not because your stance does not stack up scientifically, then on the basis that your approach is simply not a caring, humane or tolerant way to carry on.
Andrew, you just “read up”. I thought you were supposed to be giving us the benefit of your scientific expertise!
Look John, just back off! Andrew is a PhD student in ‘2D and 3D image analysis’ so he obviously knows what he’s talking about. Can’t you see he’s a scientist?!
OK! I won’t say any more.
Wrong.
It does.
I don’t care about the opinions of people who have no relevant expertise. I don’t tolerate ideas that are wrong. And humane?
I’m trying to argue in favour of a safe intervention which prevents a potentially fatal disease. You are feeding the fire of doubt which has already succeeded in killing someone — and measles isn’t a nice death.
Which of those do you think is the more humane?
just to clarify (and this is perhaps a cross post from other page here)
dr briffa,
what experimental result of set of results would convince you ‘beyond reasonable doubt’ that there is no reason to link MMR and any form of autism.
Are such a set of results possible in your mind, or will you always believe that there is reasonable grounds to believe in such a link?
superburger
Before we go on, can I ask if it’s your assertion that the current body of scientific evidence vindicates MMR with respect to autism?
Andrew
“I don’t care about the opinions of people who have no relevant expertise. I don’t tolerate ideas that are wrong.”
What expertise do you think you have that they don’t? How do you know they are ‘wrong’? You’d need evidence to assert that that just doesn’t exist.
“I’m trying to argue in favour of a safe intervention which prevents a potentially fatal disease. You are feeding the fire of doubt which has already succeeded in killing someone ” and measles isn’t a nice death.”
And I’m arguing for the appropriate scientific work to be done to properly assess whether MMR can cause autism, and if it can, how great the risk is. Is this really so unreasonable to you?
It seems to me an extraordinary situation when the credibility of a product has to be maintained by shouting people down, and pulling rank. I was looking at Mark Henderson’s whimsical musings on the autism epidemic today – autism as a fashion accessory:
http://www.timesonline.co.uk/tol/life_and_style/health/article4079455.ece
Henderson’s article is an insult to the intelligence of families who have to battle with difficulties year after year. Another example was Prof Baron Cohen’s “The rise of autism”:
http://www.independent.co.uk/life-style/health-and-wellbeing/health-news/what-are-you-optimistic-about-432696.html
Feel good stuff for people who do not have to cope with the problem. Whose agenda is this?
It’s very much up to the person arguing the case to demonstrate that they have the expertise necessary to useful argue it. It’s not my job to demolish it.
We’ve been so far over this that it doesn’t approach being funny. Suffice to say that I don’t accept arguing a true statement based on false reasoning is the same thing as being “right”.
Well, now that really depends. And what it depends on is your answer to superburger’s question: a question which you have utterly failed (or chosen not) to answer.
If you think that a small-scale study would “vindicate” MMR (which, to be fair, seems unlikely) then you imagine a much greater risk than can reasonably be supposed to exist based on current evidence, and the answer to your question is “yes: you want to put people though a scientific study to prove an unsupportable assertion and that is unethical”. If you don’t, then the answer to your question is “yes: you want to put lots of people through a scientific study to prove an unsupportable assertion and that is unethical”.
I’m sure you had a point, but I’m not sure what it was…
Andrew
The main point is very simple: the current scientific evidence does not vindicate MMR with respect to autism.
Anyone that asserts, therefore, that MMR right cause autism therefore cannont be ‘wrong’, until you can prove that (which you can’t).
“Anyone that asserts, therefore, that MMR right cause autism therefore cannont be ‘wrong’, until you can prove that (which you can’t).”
Nobody is saying that MMR can’t cause autism, just that there is no good evidence to support the assertion that it does.
The other thread got derailed by John Stone but this seems like an appropriate place to look for clarification of your position as it is directly related to the state of the evidence. In your opinion, and after weighing up the evidence, on the balance of probabilities do you think that the risks associated with the MMR vaccination outweigh the benefits of vaccination?
Do you advise parents to vaccinate? Or do you not offer any form of advice?
Why should anyone defer to the experts when they do not have a consistent story – one, in fact, which breaks down in every conceivable direction?
dr b,
my position is totally irrelevant – how can it possibly impact upon your answer?
so to repeat the question….
“what experimental result of set of results would convince you ‘beyond reasonable doubt’ that there is no reason to link MMR and any form of autism.
Are such a set of results possible in your mind, or will you always believe that there is reasonable grounds to believe in such a link?”
Ross has some brassneck. I contributed relevantly to the other thread and he’s plastered all sorts of hair splitting nonsense about whether I am “a blogger” or not. That looks like troll stuff to me.
I have to admit I cannot see why it should be JB’s job to design studies. It looks like another red-herring to me. I can actually see his predicament as a doctor, unable to cite any plausible evidence base for the policy.
superburger
“my position is totally irrelevant”
I disagree, because if your position is that MMR has been vindicated with regard to autism on the basis of current evidence, then what purpose would it serve for me to answer your question. If your mind is already made up, what the point?
So, can you clarify your position, after which we can move on.
Looks like superburger and I aren’t the only people with questions for you Dr B:
http://www.blacktriangle.org/blog/?p=1799#comment-33839
I would be grateful if any of the above posters could direct me to a UK study which reports on the clinical examination of “allegedly” vaccine-damaged autistic children (please note that epidemiological studies carry neither weight nor merit with the parents of autistic children – you see, we deal with children not statistics). To the best of my knowledge the MRC hasn’t funded any such study and I can only describe this as “an interesting omission”.
In 1992 when my boy/girl twins were fifteen months old they were given the (original) MMR. Within a month I saw my daughter descend into regressive autism – loss of eye contact, total loss of developing speech, appearing not to understand what was being said to her, etc. We have dated camcorder footage going back to when they were three months old. I’ve traced our family trees back more than four generations and I’ve yet to find anyone on the autistic spectrum.
If you “masterful theoreticians” (thank you, William Shakespeare) still can’t understand that something is happening out in the community, then I suggest that you contact any special needs teacher with more than twenty years’ experience and ask them how they used to deal with ASD children and their opinions on the current situation. Do let me know your findings.
er, dr b, my point is to see if *your* mind is already made up.
your position (or indeed your elusive answer) really can’t depend on my own thoughts on the subject.
so for, I think, the 4th time
o to repeat the question….
“what experimental result of set of results would convince you ‘beyond reasonable doubt’ that there is no reason to link MMR and any form of autism.
Are such a set of results possible in your mind, or will you always believe that there is reasonable grounds to believe in such a link?”
superburger
“er, dr b, my point is to see if *your* mind is already made up.”
Yes, it is: the current scientific evidence does not vindicate MMR with respect to autism.
P.S. Unless of course I’ve missed something that someone is going to bring here that causes me to change my mind. I did ask Anthony Cox, but what he produced was clearly not fit for purpose.
I’m pretty aware that you think there *are* reasonable grounds to believe there is a link between MMR and autism.
But you *still* haven’t answered my question:
“what experimental result of set of results would convince you ‘beyond reasonable doubt’ that there is no reason to link MMR and any form of autism.
Are such a set of results possible in your mind, or will you always believe that there is reasonable grounds to believe in such a link?”
Superburger,
What do you think of Elizabeth’s post, above? Why hasn’t the case of her daughter, and the large number of other, similar cases been investigated? Not with epidemiological studies but with a case series which looks at the actual children?
Here is a parallel example:
A particular office building presents a cluster of brain cancer cases. The health authorities, rather than reviewing the actual cases and the actual conditions in the building, do a study in another city of brain cancer rates in office workers. Finding no connection between office work and brain cancer they dismiss the cluster as a fluke.
I think parent’s of autistic children who appear to have been vaccine damaged feel like those brain cancer sufferers–dismissed without having been studied.
Without going into a mini-essay on your ‘parallel example’ it is very telling that you say that it is not fair to dismiss something as a ‘fluke’
Any student of statistics will tell you that if you take an enormous population size (office workers?) then there is a finite chance of some event (cluster of cancers) happening in that population at a given time.
It’s the same numbers-game that explains why one particular newsagent might have half a dozen big lottery winners in a short space of time.
The statisticians skill is to look at populations and see if ‘flukes’ really are flukes or something more serious is going on.
Remember, the notion that smoking could be linked with lung cancer was thought absurd until some very clever statistical analysis showed that it is almost certainly true (despite my old great granddad smoking 40 players navy cut a day for nearly 80 years and only dying by being hit by a bus.)
So, i guess i must ask you the same question that dr briffa hasn’t yet answered
i guess, minority view, I would ask you the same question, that dr briffa studiously ignores
“what experimental result of set of results would convince you ‘beyond reasonable doubt’ that there is no reason to link MMR and any form of autism.
Are such a set of results possible in your mind, or will you always believe that there is reasonable grounds to believe in such a link?”
“A particular office building presents a cluster of brain cancer cases. The health authorities, rather than reviewing the actual cases and the actual conditions in the building, do a study in another city of brain cancer rates in office workers. Finding no connection between office work and brain cancer they dismiss the cluster as a fluke.”
Sounds like an odd analogy. While I’m not disputing that there may be some factors causing cancer in the original office block this simply doesn’t have anything to do with vaccinations or autism.
Perhaps you could clarify?
What factors in the original office block do you mean? How might these cause cancer? How does cancer rates in office buildings relate to autism and vaccines? How are brain cancer, office spaces, vaccines and autism connected biologically or physiologically?
Dr B,
I intend a respectful forward-moving conversation about what can be determined. An open discussion that we can all participate in and question.
Earlier, I asked a question about designing a study which was maybe unclear or asking too much. It got no response but the question was genuine.
I state that I do not know superburger at all, but his/her question seems to reflect the thrust of my genuine concern.
Furthermore I can also very much understand that given the highly emotive subject and the tone of some posts that you may fear an ambush and so have responded to superburgers question with one of your own.
But I think that it is an important enough point to revisit.
In an earlier post you corrected me (quite rightly!) for an unscientific statement and I must respectfully do the same.
A person should surely be able to state or at least discuss the conditions under which an hypothesis could be proved incorrect. Isn’t that the ultimate strength of reason?
Indeed your point (which I completely agree with) that the current scientific evidence does NOT vindicate MMR with respect to autism relies on the very existence of the idea of falsification.
Maybe the question needs rephrased:
what experimental result or set of results would convince you ‘beyond reasonable doubt’ that there definitely is or is definitely not a link between MMR and autism?
Are such a set of results possible in your mind, or will you always believe that there is reasonable grounds to believe in such a link?”
cynic
First of all, I’m genuinely pleased that you have an open mind on the subject of whether MMR can cause autism or not.
So, in light of this, your question about further study is a good and relevant one.
I do have some thoughts on this, and am planning to devote a specific piece to this where the existing evidence is reviewed, along with my views on where future research needs to be focused.
And please let me clarify, my mind is not made up on this at all: I do think that it is possible to prove ‘beyond reasonable doubt’ that MMR can cause autism. But, again to be clear, the current scientific evidence simply does not do the job.
Thanks for the response.
I look forward to reading the future piece.
“I do think that it is possible to prove ‘beyond reasonable doubt’ that MMR can cause autism”
Right, so now you’re in good shape to answer the first part of my original question!
“what experimental result of set of results would convince you ‘beyond reasonable doubt’ that there is no reason to link MMR and any form of autism.”
superburger
As I said, your question will be the focus of an upcoming piece. You’ll just have to wait.
Dr B – will you address my questions in your forthcoming piece as well?
(In your opinion, and after weighing up the evidence, on the balance of probabilities do you think that the risks associated with the MMR vaccination outweigh the benefits of vaccination?
Do you advise parents to vaccinate? Or do you not offer any form of advice?)
“what experimental result of set of results would convince you ‘beyond reasonable doubt’ that there is no reason to link MMR and any form of autism.”
“As I said, your question will be the focus of an upcoming piece. You’ll just have to wait.”
This really is excellent news. I assume you have an approx date for this, as you’ve already put some thought into it. Could you let us know roughly when? I’ll put it in my diary.
Alas, everyone who commented on my brain cancer example missed the point. The point was that the researchers never actually studied the people with brain cancer. Just as the autism researchers haven’t actually looked at the children, diagnosed with autism, whose parents think there might be a vaccine connection. Population studies have their uses. But they cannot answer questions about specific populations with specific exposures. So the population of people working in an office building, a particular office building, may indeed have a unique set of exposures. And studying office buildings in general and office workers in general will not, most likely, pick up that unique set of exposures.
So, what are the commonalities among all the children who presented with autism whose parents think there is a vaccine connection? And why haven’t these children been studied? Directly.
“But they cannot answer questions about specific populations with specific exposures”
What about the “doctors study?”
The ‘specific population’ was doctors. And the specific exposure was cigarette smoke. The conclusion, based on statistical analysis was that smoking can causes lung cancer. Doll and Hill, BMJ, 1954, v238, p1529. If you can’t get free access, ask your local library to order it for you.
So, minortyview, I would ask you the same question the Dr Briffa is preparing an answer to.
“what experimental result of set of results would convince you ‘beyond reasonable doubt’ that there is no reason to link MMR and any form of autism.”
“As I said, your question will be the focus of an upcoming piece. You’ll just have to wait.”
PS Dr Briffa, Any approximate timescale on when you’ll have collected your thoughts on the above topic into a blog post?
this might be a dupe, sorry if is.
“Population studies have their uses. But they cannot answer questions about specific populations with specific exposures”
What about the famous “doctors study.” The population was doctors, and the exposure was cigarette smoke. The conclusion that smoking is linked to lung cancer. Doll and Hill, 1954, BMJ. (your local library can get you a copy if your stuck for access)
i suppose ask you the same question that dr briffa is (soon, we hope!) going to answer.
“what experimental result of set of results would convince you ‘beyond reasonable doubt’ that there is no reason to link MMR and any form of autism.””
And in addition, if you still want to think about cancer cases in an office building, how would you be able to tell that the cancer cases weren’t simply a random event?
Superburger, if you don’t study the actual brain cancer cases, on what basis will you conclude anything about these brain cancer cases?
The children with autism haven’t been studied. So on what basis do you conclude that their autism is not connected with this, that or the other? The data you need to eliminate stuff doesn’t exist, because it hasn’t been collected. The reason is hasn’t been collected is because the children haven’t been studied. And the reason they haven’t been studied? See the Bernadine Healy interview.
er, minority view, I haven’t expressed any opinion about MMR and autism. And tbh, it is a complete irrelevance what I think. I’m not a media nutritionist whose opinion might be of some interest to the general public.
Also, did you consider my comment about the Doll and Hill study w.r.t. the use of statistical analysis to show evidence of links between exposure to disease?
you say
“The data you need to eliminate stuff doesn’t exist, because it hasn’t been collected”
What data do would you like to see collected? And having collected this data, I would ask you again (and of course, Dr Briffa’s blog on this is still keenly awaited):
“what experimental result of set of results would convince you ‘beyond reasonable doubt’ that there is no reason to link MMR and any form of autism.”
Minority report raises a very valid point which should be considered carefully, I think. It worries me that the point-scoring that is going on might obscure a careful consideration of the ways in which epidemiological and case-by-case studies should be complementary. Marching under the banner of one cause or the other doesn’t really illuminate (we lead to the preposterous situation of somebody apparently writing a blog in the hope that someone else will respond to it and thus be shown up in some way).
Anyway, MinorityView, well-worth pursuing your idea. Thankfully people are doing so. Type “Autism” and “Immune” into PubMed – you’ll get a lot of hits (8 pages of study headings). Of course, doing literature searches is a difficult business and drawing conclusions about what they show is very complex. There is very rarely a single killer experiment that asnswers the question one way or another and so we are forced to distil information and weigh up risks over many small pieces of information. I certainly wouldn’t claim that I have any more than average expertise in this weighing up process but I don’t think that the studies done so far indicate any link between the vaccine and the spectrum of autism. You may well think differently when you’ve been through the same literature – but I just wanted to draw your attention to the fact that there is indeed a scientific literature in the area that you mentioned and to applaud you for highlighting its importance
Very well put Paul.
Paul
Can I ask you to clarify something?
It your assertion that the evidence (as you see it) suggests that MMR is not linked with autism (please correct me if I’m wrong on this).
But if I’m right, is it also your view that the quality of the evidence we have at present vindicates MMR with respect to autism?
Dr Briffa
Your question is very acute.
Perhaps I could sharpen my position a little: The evidence, as I see it, does not support a causal link between MMR and autism.
In my view, the quality and quantity of the evidence aginst a causal link outweighs the quality and quantity of the evidence in its favour. By quite a margin.
I think that your own position (forgive my presumption) is philosophically a sound and admirable one (after Lord Byron – “Deny nothing but doubt everything”) and I would agree that there is not “no risk” of a link (i.e. I may be wrong). But, from the pragmatist’s point of view, ww are often in the position of recognising that a course of action may have a risk (real or asserted), assessing the risk of taking that action, assessing the risk of not taking it and making our decision accordingly. On the basis (quality and quantity) of extant evidence, I found this an easier decision to take with my children than I’d ever imagined before began to sift through the empirical and review evidence.
I think everyone would concede that it’s impossible to ‘prove’ any scientific hypothesis; only possible to add more and more evidence of increasing quality. Smoking may not be linked with lung cancer, but there is an overwhelming body of evidence to say that it does, there is little reason to doubt that hypothesis any more (although we’re always alive to the possibility that it may be wrong).
Either MMR is linked to autism, or it is not. Both of these options are fair hypotheses.
I’m still fascinated to know what evidence would convince Dr Briffa (and indeed MinorityView) that the hypothesis “MMR is not linked to autism” is valid, and beyond any “reasonable doubt”.
Dr Briffa agrees (I think) that such a set of results is possible, all that remains to be seen is if he could share his thoughts on the topic!
I appreciate Dr B is a busy man but I can’t help but think that ‘time crunch’ isn’t the reason why he hasn’t answered the simple, direct questions that have been put to him in a simple, direct manner. There just seems to be a general reluctance to engage at anything other than a superficial and semantic level. Which is ironic given his comments below (May 31st @ 3.13 p.m.). http://jdc325.wordpress.com/2008/05/30/more-briffa/#comments
Would it be too much to ask to answer the points I’ve put to you in my first comment above? I mean, isn’t that what the comments section of blogs is all about, really – debate. But if it’s all a bit one-sided and people don;t have their questions answer, it’s all a bit pointless, isn’t it?
ross
Time is a factor, but the other thing that will hold this up is the belief I have that the arguments put forward by people who assert MMR is vindicated with regard to autism need further unpicking. It’s partly the unscientific intransigence of individuals just like you that makes this necessary, I think.
I suppose I should thank you for your persistence: it has certainly helped highlight for me just how spurious the ‘MMR is safe with respect to autism’ arguments are.
So, with regard to the question of the sort of evidence that would prove beyond reasonable doubt that MMR does not cause autism, I say all in good time. There’s plenty more that needs to come out before I move on to this.
“but the other thing that will hold this up is the belief I have that the arguments put forward by people who assert MMR is vindicated with regard to autism need further unpicking.”
Why would that stop you stating whether or not you think the benefits of MMR outweigh the risks? Or whether you advise parents to vaccinate or abstain from offering advice.
Simple questions requiring simple answers.
Oh, and an example of my unscientific intransigence would be nice too!