Magnetic Sex Appea… Shhhh

March 4th, 2006 by Ben Goldacre in alternative medicine, bad science, magnets, placebo | 91 Comments »

Ben Goldacre
Saturday March 4, 2006
The Guardian

If there’s one thing that irritates a scientist, it’s not knowing. This week, the Prescription Pricing Authority decided to authorise magnetic bandages for ulcer treatment on the NHS: and I have no idea why. They won’t tell me what the presented evidence was, because that’s not their policy. Shhh. It’s a secret.

And you thought science and medicine was about openness and evidence? So I trogged over to the Magnopulse site: when I could get through, that is, for hours all I got was: “This site is unavailable because it is too busy,” so business is good.

Sniffing around for data I found, to my immense delight, that they also have a special magnet for women to wear: “Wearing mn8 also boosts your body naturally, giving you softer skin, shiny hair and stronger nails.” It sounds a bit like the Winalot TV ads to me, but that pales into insignificance next to the Magnetic Pet Coaster that goes in your dog bowl.

Did the dog bowl magnet feature in the evidence they offered to the PPA? We will never know for sure, but the claims are equally grand. “They will love the taste.” Why?

Because “Magnetic treated water is more natural. Using a pet coaster ensures that your pet receives maximum benefit from their drinking water”.

I want one. Why do my dog and my girlfriend always get special treatment? “Given the choice,” they go on, “your pet will always choose to drink magnetic water, they can tell the difference.”

Now, stats can be complicated, I realise: but “always” is a very easy thing to do the maths on, in one afternoon, with one dog and two bowls. If Derek Price of Magnopulse Ltd (one million sales so far) wants to get in touch, I’d very much like to help him verify that claim.

Does the hyperbole end there? I found the magnetic bandage in question. It’s hard to miss, there’s a big picture of the 4Ulcercare box plastered with the words: “NHS trials proved conclusively that Ulcercare helps the body heal chronic leg ulcers. Naturally.”

“Proved conclusively,” again, is a rather grand claim, and I’m hoping for evidence. But all I can find is a small pilot study with 26 patients, and a customer survey. Can that be conclusive proof?

Magnet therapy has been heavily investigated elsewhere, of course, and the evidence is not good. It’s easy to tell, if you’re in a “blinded” trial, whether you got the real magnet or the placebo one – whether you want to know or not – because magnets stick to your fridge, or your keys when you get them out of your pocket. Trials that haven’t accounted for this are worrying, while trials which hide the magnets cautiously show that they’re no better than placebo.

And that’s the key, of course. Because magnet therapy might draw a blank, but placebos are very effective, and popular. There was an ingenious trial just two weeks ago in the BMJ, comparing a placebo sugar pill against a placebo ceremony, themed on acupuncture, and it found, again, that there are different grades of placebo. Because, of course, placebo is not about a sugar pill, it’s about the cultural meaning of the treatment, the interaction, the setting, and the ritual.

This is something that has been vanquished from modern medicine, where we champion informed consent and patient autonomy over efficacy. I’m completely embedded in that idea. For all I know we only do it to fulfil our own professional fantasies of rationality. Maybe we should just get over ourselves and start confabulating to patients about evidence and theory like alternative therapists do.

In fact, maybe that’s what’s happening here. The PPA, to be fair – and they were allowed to tell me this – only assess on things like cost-effectiveness, and safety. But I honestly suspect that this might be the first time in history that something has been embraced by the NHS, with no compelling evidence of efficacy, knowing at the time that its effects may only be placebo. This could be the beginning of a very weird cultural shift: just so you know.

Please send your bad science to bad.science@guardian.co.uk


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91 Responses



  1. Martin said,

    March 6, 2006 at 1:33 pm

    What I object to with these magnetic bandages is the cost. They may only cost a little more than normal bandages, but they still cost more. This is removing money from an already cash-strapped public service to pay for treatment which has no medical benefit (if it’s no better than a placebo, then there must be no ‘medical’ benefit).

    Why should the NHS pay for these bandages? Why should the NHS even pay for clinical trails or the PPA? Surely Magnopulse, if they stand to make such a huge profit from these magnetic bandages, should be funding sufficient trials to prove conclusively that the bandages have a medical benefit. If they can’t prove this then the NHS shouldn’t pay for them. If they can, then the PPA or NICE (or whoever) can give them a green light.

    The same argument goes for alternative therapies available on the NHS, eg, the Bristol Homeopathy hospital (see Bad Science November-ish). I’m sure the surviving relatives of hundreds are glad that operating theaters and wards are being closed up and down the country so that the NHS can fund such rubbish.

    Unfortunately, this argument does begin to lose some ground when you talk about drugs like Herceptin, which has a medical benefit, but patients suing for access to it are forcing the NHS to spend money on legal fees.

  2. ACH said,

    March 6, 2006 at 3:10 pm

    I don’t think the argument loses ground – the Herceptin (an other drugs subject to postcode prescibing) issue is a good example of why non-proven therapies shouldn’t be available on the NHS. If people want magnetic or herbal placebos, put them in the queue for NICE and make people wait. Though I also don’t see why NICE should spend money on evaluating placebos when they are dragging their feet over Herceptin and even more expensive therapies (some orphan drugs) which have been through RCTs and are licensed, but patients are still being told they can’t have them because they’re too expensive.

  3. Mr Magoo said,

    March 6, 2006 at 3:52 pm

    Don’t want to get into a Herceptin argument, but the main problem is a licensing one – if a drug isn’t licensed to do something, technically speaking doctors shouldn’t prescribe it for that condition – Herceptin currently isn’t prescribed for early stage breast cancer (see for yourself – SPC is available freely online at emc.medicines.org.uk/ and search under Herceptin) … from what I understand Roche are desperately trying to get it licensed for that very thing right now, but until they do doctors are completely in the right now to prescribe.

    As for magnetic bandages, they sound excellent… and if they ‘create a pleasing cosmetic effect when worn near the penis’ (I’m sorry, but the whole bandage thing is actually a bit of a turn off), how long until we see magnetic condoms? 😉

  4. Martin said,

    March 6, 2006 at 3:57 pm

    I’m waiting to see which of the national newspapers goes for this story: Beer fights heart disease: official (www.theregister.co.uk/2006/03/06/beer_effects/)

    Fortunately the report on The Register makes it clear that it’s an in vitro experiment, but how long do we think it’ll take someone to write a lovely puff-piece on the health benefits of beer? Unfortunately, you don’t need to read too far into the piece to see that non-alcoholic beer produces the same effect – but do we really wat to drink Kaliber?

  5. Ben Goldacre said,

    March 6, 2006 at 5:31 pm

    I think, having read the comments, I may have spotted a way to blind test magnetic bandages, in keyrawn’s post about the patent information, I quote

    “the treatment of skin ulcers when the negative pole (sic) is placed adjacent a user’s flesh”

    So the blind trial consists of two sets of bandages, where, to quote Doctor Who, you “Reverse the polarity” of the second set. According to the patent, these should not work, but the magnets will still stick to fridges etc.

    pete, that is absolute bloody genius.

  6. Ben Goldacre said,

    March 6, 2006 at 5:42 pm

    morag, that forum link is great, were you rolfie? do you know who she is?

  7. Pete said,

    March 6, 2006 at 7:21 pm

    Ben Goldacre said,
    “pete, that is absolute bloody genius.”

    Why thank you Ben (takes a bow)

  8. Natalie said,

    March 6, 2006 at 8:57 pm

    not debating herceptin…but its actually only useful for a very small percentages of breast cancers which have amplification of a certain gene (ERBB2). what makes me mad about this whole situation is when they parade these bandages on this morning, a researcher had worn it for two hours and apparently his painful shoulder was feeling alot better. once again i find myself yelling at the tv…”the plural of ancedote is not data!!”

  9. Melissa said,

    March 6, 2006 at 10:37 pm

    Wow, Morag, this Hpath thread is great reading! Thanks.

    It’s really interesting how quickly homeopaths resort to emotionally-charged attacks in lieu of rational discourse. Probably because rational discourse isn’t part of their extensive training.

  10. Ben Goldacre said,

    March 6, 2006 at 10:45 pm

    yup, you think if you’ve seen one flame war, you’ve seen them all, but the hpath page absolutely made my day. the smugness was too much. are there many more where that came from?

  11. keyrawn said,

    March 7, 2006 at 12:03 am

    Mr Magoo should look at Google. He will find “Magnetic condom,
    US Patènt # 6863070 : Invèntors: Shapiro; George (25 Old Sprain Rd., Ardsley, NY 10502); Nigro; Anthony (56 Forest Ave., Cortland Manor, NY 10567)
    Appl. No.: 417274 Filed: April 16, 2003
    The patent gives full details of the condom and its benefits. Ugh!

  12. Melissa said,

    March 7, 2006 at 1:43 am

    I can just imagine a whole new fetish community being birthed by this invention.

    Ugh. I’d rather imagine something else… anything!… Help…

    (thinks about kittens)

  13. Tessa K said,

    March 7, 2006 at 12:08 pm

    What metal are piercings made of? Nothing magnetic I hope, otherwise there could be some unfortunate incidents with the magnetic condoms.

  14. Ian said,

    March 7, 2006 at 12:22 pm

    piercings are made out of precious metals (gold, silver, platinum), plastics (eg ptfe) or surgical steel, which is not affected by magnets enough to worry about. I have several piercings and have yet to be dragged toward passing large magnets.

    They don’t get picked up by metal detectors, either… however, I’m not sure if they mess up MRI – anyone know?

  15. Mongrel said,

    March 7, 2006 at 1:29 pm

    “morag, that forum link is great, were you rolfie? do you know who she is?”

    Rolfe is a regular over at the JREF forums. Here’s a thread concerning Rolfes’ Voodoo Vetinary website (link in first post) forums.randi.org/showthread.php?t=47441 and the ‘fun’ of dealing with Homeopaths.

  16. Andrew Clegg said,

    March 7, 2006 at 5:18 pm

    Ian, I’ve had fMRI, and they made sure I’d taken all my piercings out first (easy as I don’t have any). I think the field strength is so great that even alloys with a small proportion of ferromagnetic material will get pulled out of your skin.

    Andrew.

  17. Francois Gould said,

    March 7, 2006 at 7:14 pm

    ok, just one point. Sorry Dr Goldacre, but you’re comitting Bad History. Informed consent and patient autonomy are very recent developements indeed in the history of modern medicine. The shift you correcty identify that banishes the role of ritual etc.. is a change in the perception of disease that occurs around the end of the XIXth century. In the new perception, symptoms (ie the personnal experience of disease) are viewed as the manifestations of a single causal agent (the germ). As a result, medicine and the doctor no longer need to attend to the patient and his experience of the disease beyond using it as a diagnostic tool. Informed consent and patient autonomy are in many cases the result of a patient reaction against the dehumanising nature of early modern medicine.
    This does not excuse the NHS, at the very least they should provide theevidence on which they license their stuff, particularly if they genuinely believe on informed consent.

  18. Alex said,

    March 7, 2006 at 8:04 pm

    You people obviously seem to have a good idea of what you are talking about. Correct me if I am wrong Ben, but havn’t I seen Rolfie around here. She certainly sounds like she was from around here. Keep up the good work and slap those silly quaks silly. ;-D

  19. Ben Goldacre said,

    March 7, 2006 at 9:21 pm

    francois, i’m sorry you’ve a bee in your bonnet about doctors being horrible, but the point i was making was this: not being able to lie to the patient is a new problem created by the conflict with patient autonomy and informed consent. it’s only in the last generation that you’ve had doctors writing out huge surgical consent forms, telling patients their diagnoses instead of “holding back the full truth for their own good”, explaining treatments, what they are, how they work, asking their opinion, etc, and all that’s obviously incompatible with lying to patients about the options. i fail to see how the untenability of lying to patients is connected to your fanciful ideas about 19th century germ theory, or how horrible doctors are.

  20. glowinginthesun said,

    March 8, 2006 at 8:20 am

    Quote:
    “Here’s a counter argument for the “Big Pharmas are only in it for the money” statement. AstraZeneca has withdrawn plans to launch the blood thinning drug Exanta while it was still in the clinical trial stage …”

    Well, this is definitely no counter on Big Pharma and money, as the Germans apparently weren’t that lucky. Here it was released to the market and about two weeks ago withdrawn due to serious liver damage – which had been quite obvious during the clinical trials. So about 2000 patients were potentialliy harmed. For the money – and only for the money.

    I’m an german pharmacist, btw.

  21. Mark Gould said,

    March 8, 2006 at 11:13 am

    You will be delighted to hear that not all government agencies are hoodwinked by these people. The Office of Fair Trading has just announced that it has started High Court Proceedings against Magno-Pulse for their misleading advertising.

    The full press release is at www.oft.gov.uk/News/Press+releases/2006/47-06.htm

  22. Ben Goldacre said,

    March 8, 2006 at 11:39 am

    That is properly the funniest thing ever.

    OFT seeks court order against magnetic goods manufacturer

    47/06 8 March 2006

    The OFT has issued High Court proceedings against Magno-Pulse Limited, and its officers Derek and Wendy Price. It is seeking an injunction against them under the Control of Misleading Advertisements Regulations 1988.

    Based in Bristol, Magno-Pulse Limited is a manufacturer and retailer of magnetic therapy products for humans and animals, including back and neck wraps, magnetic drinking coasters and pet beds. The OFT is seeking an injunction preventing publication of advertisements making the following claims about the company’s products:

    * the products have a therapeutic effect, caused by a specified physiological mechanism, due to the magnets they contain
    * the therapeutic effect of the products, due to the magnets they contain, is clinically proven or established by scientific trials, or is widely accepted in the scientific or medical communities
    * unqualified claims the products have a therapeutic effect and/or that wearing products containing magnets will always produce such an effect, due to their magnets
    * that products magnetise or ionise water as a result of the magnets they contain.

    Magno-Pulse Limited contends that the advertisements are not misleading and has refused to stop publishing adverts making these kinds of claims. Accordingly, the OFT has issued proceedings so the courts can decide the matter. Magno-Pulse Limited has indicated it intends to defend the proceedings.

    The worldwide market for magnetic therapy products for treatment of humans has been estimated at around £3bn a year. The size of the market for these products for use on domesticated animals such as dogs and horses is not known, but would be in addition to this figure.

    Christine Wade, Director of Consumer Regulation Enforcement said:

    ‘Where advertisements claim products have therapeutic effects it is important they do not mislead consumers. The OFT is asking the High Court to decide if Magno-Pulse Limited’s advertisements are misleading.’

    NOTES

    1. Whilst the OFT has issued proceedings and Magno-Pulse Limited has indicated it intends to defend them, it is for the High Court to decide whether the relevant advertisements are misleading under The Control of Misleading Advertisements Regulations 1988 (the CMARs). No date has yet been scheduled for the High Court hearing.

    2. The CMARs came into force on 20 June 1988 implementing the EC Directive on misleading advertising. The CMARs aim to protect consumers and businesses from misleading advertisements and advertisements that make prohibited comparisons. The OFT’s main role under the CMARs is to support and reinforce the existing advertising controls exercised by other bodies, such as the Advertising Standards Authority (‘the ASA’), not replace them. The OFT will usually step in where action by those other bodies has not resolved complaints about an advertisement and it is in the public interest that the OFT should act.

    3. The ASA referred Magno – Pulse Limited’s advertising to the OFT for consideration under the CMARs after the ASA had received, and sought to resolve, complaints about that advertising.

    4. The OFT can only act under the CMARs when a complaint about an advertisement is received. To come within the scope of the CMARs, and be restrained by an injunction, an advertisement must be misleading (i.e. it must deceive or be likely to deceive the recipient and be likely to affect their economic behaviour, or for those reasons harm the interests of a competitor), and be published in connection with a trade, business, craft or profession, in order to promote the supply or transfer of goods or services, immovable property, rights or obligations. The OFT can take action against anyone appearing to be concerned or likely to be concerned with the publication of a misleading advertisement.

  23. Stever said,

    March 8, 2006 at 11:55 am

    hahahaha. thats fucking brilliant!

    …and they are going to defend themselves in court. What a joy thats going to be.

    but BLOODY HELL – the market is worth 3 BILLION!!!

    is this is linked to the Guardian piece btw?

  24. Martin said,

    March 8, 2006 at 12:36 pm

    OK, so Magno-Pulse are being touted by the PPA and sued by the OFT.
    That’s joined-up government for you!

    Note: OK, so the PPA and OFT aren’t government, they’re quasi-autonomous non-governmental organisations, but “that’s joined-up quangos” doesn’t have the same ring.

  25. ACH said,

    March 8, 2006 at 3:17 pm

    So, who’s going to tell the PPA? It would be a great result if they actually withdraw their approval, and let funds be spent on REAL therapeutics.

  26. ACH said,

    March 8, 2006 at 3:22 pm

    Actually, I wonder if “But it’s approved by the NHS” is going to be part of the defence.

    If the PPA has shot itself in the foot, do you think a magnetic bandage would help?

  27. Francois Gould said,

    March 8, 2006 at 9:32 pm

    Ben,
    fair point, I was a little off the mark in my comment. The point you make about how medicine is practiced currently is valid. However, the fact that modern medicine refuses to use the placebo (indeed the very fact that we have described such a thing as the placebo effect at all) is due to a change in the perception of disease and its treatment that makes disease eradication (to some extent), independant of symptom aleviation. This is not a fanciful idea, it’s documented historical shift (look at the records kept by XIXth sentury French doctors in hospitals, who did not intervene much on their patients in order to observe the progression of disease and thus associate different symptoms together as products of a single entity). My point, and it’s probably a rather trivial one, is that modern medicine’s aversion to the placebo is older than informed consent.
    incidentally, I haven’t had very many bad experiences with doctors beyond the run of the mill oerworked NHS variety. On the whole they are lovely people and I even contamplated becoming one, but opted for Evolutionary Biology instead.

  28. Ben Goldacre said,

    March 8, 2006 at 9:38 pm

    i’m sorry, but again, that’s nonsense. the “change in the perception of disease and its treatment that makes disease eradication (to some extent), independant of symptom aleviation” sounds nothing like the diverse forms of above all pragmatic medicine which i see practised all around me every day. in fact, this description sounds like the hopeful fancy of somebody studying the history of medicine, with no experience of how everyday practical medicine is practised, who wants to make a pet theory ring true, and the contents of some 19th century french doctors notes are neither here nor there. in fact, they’re so neither here nor there, that i have to ask: is this a very subtle and elaborate joke to wind me up?

  29. Dave said,

    March 9, 2006 at 4:45 am

    Ben, I think a good topic here as a spin off would be the obvious flaw in the pharmaceutical industry where companies are permitted to selectively file research into drugs.
    So in the case of anti depressants, where 1/3rd of studies showed a benefit, 1/3rd showed no change and 1/3rd showed a worsening, they only filed the first 1/3rd of the studies showing a benefit.

    Subsequent research shows anti depressants are no better than placebos.

    A simple rule obliging drug companies to file all studies conducted would improve the process in this area.

  30. Martin said,

    March 9, 2006 at 7:59 am

    Great idea to force drug companies to publish the results of all studies, but how are you going to police it? The drug companies will invest in either more document shredders or more creative writers for the study summaries, which are the only bit most people read.

  31. Pete said,

    March 9, 2006 at 9:41 am

    Martin Said
    “Great idea to force drug companies to publish the results of all studies, but how are you going to police it?”

    Simple, set up an independant organisation that runs the trials, probably one run by some worldwide group like WHO, insist that no drugs can be authorised until this group has passed it with their clinical trials.

    Fund it with the money the Pharma companies save by not having to run the trials themselves!

  32. james L said,

    March 9, 2006 at 10:56 am

    Pete – that is a good idea but how on earth are you going to fund and run something like that. Even a small phase 1 trial costs £1M and involves 20+ staff to run. An organisation capable of running all of the clinical trials in the world would be even larger than the WHO and have a larger budget. Even if it were possible to set up, with no competition this would soon become a bureaucratic behemoth.

    I do agree that all results must be published (at the drug companies expense) and this could easily be implemented as all trials have this in their budgets anyway.

    And to my actual point- did anyone see the discussion of the magnetic therapy on the BBC news this morning. It was one of the worst ‘discussions’ I have seen with a seller of magnets claiming that it was the natural progression from MRI scans as “that involves magnets” and that “there is already magnet therapy as people are having massive doses of magnetic therapy when they have a cat scan, people have reported that they feel better after a scan.”

    (apologies if I am not word perfect but that sums up the quotes pretty well.)

    I nearly choked on my cornflakes!

  33. Andrew Clegg said,

    March 9, 2006 at 11:08 am

    I’m sure I’ve heard of a proposed initiative whereby pharma/biotech companies have to register all their clinical trials in advance, so if there’s a negative result and they don’t file results, that becomes glaringly obvious to the regulators and the public. Hmm, six trials registered, only two (positive) results filed, wonder what the other four were?

    I don’t have a reference for that though, maybe someone else can fill in more details.

    Andrew.

  34. Ben Goldacre said,

    March 9, 2006 at 12:14 pm

    publication bias towards only positive trials is nothing compared to covert duplication of positive data:
    www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9310564&query_hl=1&itool=pubmed_docsum

  35. Alex said,

    March 9, 2006 at 5:08 pm

    That last comment…ermm.

    On the subject of Magno-Pulse being sued by the OFT. Sweet! Are there any other examples of bad science being taken to court?

  36. Alex said,

    March 9, 2006 at 5:23 pm

    So I am not the first one to suggest testing bas science in the courts,

    “Letters

    Thursday May 26, 2005
    The Guardian

    Court out

    Bad science is compulsive reading, but is there no redress against the ridiculous claims Ben Goldacre exposes? I would like to see a Lawyers Against Bad Science (Labs) group set up to test these misleading ads in a court of law.
    Kurt Weithaler
    Norwich ”

    Found this on this site. Very off topic, I know. But…any comments?

  37. Pete said,

    March 9, 2006 at 9:46 pm

    James L

    As I said, fund it with the money Pharma are no longer spending on doing there own trials. I think however Andrew Cleggs idea would be easier to implement. There would have to be a strict rule though that no “unregistered” trial could be used as evidence!

  38. coracle said,

    March 10, 2006 at 9:36 am

    Andrew, Ben et al,

    As far as registration for clinical trials goes, it seems to be the journals that are pushing for this. Take a look at the links below (nature reviews drug discovery requires a subscription unfortunately). Basically, if a company wants a trial published it has to be registered in advance. This at least is the first step in getting all trials published.

    As far as 2 of six trials being published, it may be related to the stage of trial. I’m guessing that phase I (safety in healthy volunteers) and phase II (efficacy) are much less likely to get published than phase III?

    NEJM comment

    NRDD article

  39. Delster said,

    March 12, 2006 at 11:32 pm

    Pete,

    i think your idea may have merit. After all at the moment new drugs have to go through a seperate approval process for the various countries / regions that they are to be marketed in.

    What would be a good way to work it is the Pharma companies develop the drug (or whatever the treatment is to be) more or less as they do at the moment but the final clinical trials get carried out by the WHO and, if approved, this then carries approval for all counties.

    This would actually save time and a certain amount of money on the individual approvals processes as well as making sure drugs are properly tested and are better than just placebo

  40. Robert Carnegie said,

    March 20, 2006 at 1:15 pm

    Perhaps they are quite good bandages with or without magnets. No doubt a well made wound dressing is helpful in healing, particularly when the patient is pursuing an active life in the meantime and is at risk of damaging or contaminating the wound. I can’t see the magnet being especially helpful, but aren’t there bacteria which stick to magnets? So they won’t stick to the patient. but of course you want evidence, you scientist you.

    Maybe a large lump attached to a wound stimulates blood or other fluid flow by bonking against the wound as you move around.

    Let’s not overlook the possible placebo effect of an electromagnet. I want a bandage with blinking LEDs and a gentle caring bleep once a minute – when I need one, that is. How often can the NHS give you that kind of attention? On Star Trek these days you get some kind of electronic tiara. It’s techy and it’s elegant.

    It’s fascinating that the anti-impotence magnet treatment is owned by Ladycare. I haven’t found that they do, particularly. As for an effect on intimate jewellery, I think it could be either delightfully stimulating or extraordinarily painful, and given how magnetic force varies with distance it could go from one to the other quite suddenly. This time the electromagnet needs an off-switch.

    Does that thing that you put on your head really work? Not my Star Trek thing, I mean the one that looks as though they made it out of about four wire coathangers on Electric Blue Peter.

  41. geoffd said,

    March 29, 2006 at 2:39 pm

    I spent quite a lot of time wrapping rings of rare earth (i.e very strong) magnets around cocoa trees in a glasshouse at Reading University. It was actually about NMR but I am now wondering if the trees I selected in the not altogether successful series of experiments have prospered more than the others. Do trees know about the placebo effect?