How do you take your Placebo… Clear or Cloudy?

I recently find myself debating the placebo effect a lot more, and as usual I often find myself having some rather lively and interesting discussions on it. Such as, does it exist in therapy, if so, should we utilise or harness it more, is it ethical to do so, and does it work. So I thought I would write a quick little blog on giving my own views and opinions on the placebo effect.

So first what do we mean by the term placebo and/or the placebo effect?

Well take a look at this three minute video it explains placebo brilliantly, its clear, concise and entertaining. It even contains the phrase “all shinny and shit

Welcome back, so hopefully that explained things a bit more, but I still think there can be confusion at times around the definition and description of placebo, for example a common definition is…

A treatment that has no physiological effects and is used only for a patients psychological benefit

However, another definition can be…

A beneficial effect following a treatment that arises from a patient’s beliefs and expectations

Now although similar, these two definitions describe two different things! The first describes a placebo. The second a placebo effect. This subtle difference in definition is crucial in my opinion.

The first definition of a placebo is what I would class as a ‘clear’ placebo. This is when there is absolutely no question that there are NO physiological effects at all from an intervention or treatment, for example, taking a sugar pill in a drug trial or using toothpicks in an acupuncture trail. This clearly means that any positive effects are only due to a patients psychological responses.

The second definition of a placebo effect is what I would class as a ‘cloudy’ placebo, This is when there maybe ‘some’ small physiological effects but they can be increased or ‘amplified’ by a patients psychological responses.

Now in the world of physiotherapy I’m under no illusion that placebo effects EVERYTHING we do, from manual therapy, taping, needles, electrotherapy and even exercise.

Patients expectations and beliefs of seeing a health care professional in a clinical environment will always produce a placebo effect to a lesser or greater extent in people. Most therapists tend to be caring, warm, compassionate, empathetic and, dare I say, rather attractive individuals, so they produce placebo effects even before they have have done or recommended anything.

However, I do think it’s hard to say we have any ‘clear’ placebo treatments in physiotherapy, although I dont disagree there is a lot of quackery around them.

It can be argued, and it is often is, that there is always some physiological response with everything we do. For example we can’t give a placebo exercise without it creating some sort of physiological response to the cardiovascular and neuromusculoskeletal systems. We can’t give a placebo manual therapy treatment without it creating some sort of peripheral or central physiological response due to interaction with the skin and its neural and vascular systems.

This means that ‘clear’ placebo in physiotherapy is pretty much impossible, we dont have any sugar pills.

However, physiotherapy certainly does have lots of ‘cloudy’ placebo effects! There are many treatments and techniques that do have some small physiological effects that can be ‘amplified’ and ‘increased’ by a patients beliefs and expectations to create more significant and meaningful effects that have nothing to do with the treatment.

For example, lets look at manual therapy, it doesn’t matter which one, let’s say good old standard soft tissue massage. As I mentioned, touching the skin will undoubtably create some changes in the central nervous system and some small superficial physiological effects (source). But patients past experiences, beliefs and perceptions of what massage feels can or could do will enhance these effects (source)

And it’s not just manual therapy, let’s look at acupuncture. Again we know sticking a needle into someone will cause a physiological response, it’s been seen in fMRI studies (source) but are these physiological neural effects significant?

I doubt it!

Place anyone into an fMRI machine and do anything to them, you will see changes light up. Are these physiological changes meaningful and relevant to the condition we are trying to address? Thats the harder question to answer, but let’s not get into that debate now, instead let’s just stick to looking at if these small physiological effects seen on fMRI of being pricked with a needle are enhanced by placebo effects.

Well simply put, yes they are!

Many studies have shown this. One of my favourites is this one done by the prominent, some say infamous placebo researcher Ted Kaptchuk. He gave a group of patients sham acupuncture with minimal therapist interaction and information, but another group were given exactly the same sham acupuncture, but with what he describes as ‘schmaltzy’ care by the therapist for 20 minutes. That being lots of empathy, warm, caring, shared emotion with detailed information about what acupuncture is expected to achieve, and although both groups having exactly the same sham treatment the group which had the extra clinican attention had significantly increased positive results comapred to the other group.

And there are many, many other studies that show similar results. Lots of physiotherapy treatments are enhanced when a patient has greater expectations, beliefs or positive past experiences about the treatment, such as taping (source), massage and manipulation (source), even rehabilitation exercises (source) and even ice baths (source)

But now we get to the crux of the argument I find myself having the most when discussing the placebo effect! Should we be looking to actively promote, harness and increase the placebo effects?

Well, if according to Ted Kaptchuk just being a nice, caring, considerate or ‘schmaltzy’ therapist promotes a placebo effect and gets a better result from a back rub, a joint poke or even a bit of exercise then of course yes, enhance that effect, be a nicer person, nothing wrong with that, I would activiely encourage that, but more importantly there are no ethical conflicts from just being a nicer person, and no risks to the patient!

But to harness a placebo effect by embellishing, exaggerating or just bullshitting the benefits of what a treatment can do is, in my opinion, simply unethical and wrong. It involves the need for a clinician to decieve and deliberately mislead, misinform and dupe patients. This means they cannot make a fully informed decision, and so informed patient consent is not gained. This fundamentally breaks a key code of our professional conduct and destroys the bonds and trust between the clinican and their patient.

Now, there has been a lot of debate around this, many argue that they are not misleading or duping patients as the research and evidence is so inconclusive on many areas within physiotherapy, and a lot doesn’t show with any certainty what the effects or outcomes of a lot of treatments are, and I agree, there are many grey areas.

So in situations like this, some say that its only fair and natural for them to use their own interpretation of the research explaining what the expected effects and outcomes will be.

I disagree. We must not let our own personal opinions, interpretations and so biases interfere with patients choices. We must try and give the patient the facts and allow them the chance to make an informed decision based on these as best as we can present them in an unbiased way.

Now this is much easier to say than do, bias is everywhere and its strong. I have to bite my lip, hard, everytime someone asks me about acupuncture or stretchy tape so as not to let my own bias against them destort the patient from deciding if they want to try them.

So what do I say in situations like these where my own bias is against a treatment but the patient has asked for some more information or directly requests it? Well its simple, I just say whats is known, and that is usually along the lines of we just dont know…

Those four words are not used often enough… ‘we just dont know’

I will of course give a little more information, clear up any misunderstandings or incorrect beliefs, but thats about it. If then patient wants to continue with said modality then fair enough, if not, also fair enough!

Sounds a bit long-winded for a back rub or some stretchy tape I understand that, but I think this open, honest discussion with patients around any treatment is fundemental.

But does this long-winded approach do me any favours? Am I potentially removing the positive effects of the placebo effect? Well possibly yes, but through choice I’d rather practice this way, it allows me to sleep at night and be at peace with my own ethics, I have no desire to be a promoter or a pedaler of placebo.

So there you go, my own personal views on placebo and placebo effects, clear and cloudy. I’m sure some will disagree, and a few may argue that if there is no harm or risk to the patient, why not try to harness placebo and its effects?

Well in a nutshell I think it comes down to this, utilizing or harnessing placebo ‘effects’ from a treatment which has other known physiological effects, be they large or small, is possibly ok if clear explanation is given, but promoting and using placebo without any clear physiological benefit is fraught with ethical dilemmas and in my opinion destroys the patient / clinician relationship!

I’d be interested to hear your views on this!

For more on the ethics of placebo take a look at @NeilOConnells blog on it here over at Body In Mind.

As always thanks for reading






  1. Hi,
    I’m wondering what your thoughts are on placebo actually having a physiological effect? There was an interesting program on ‘Horizon’ that detailed a study where at high altitude athletes were given fake oxygen and display increased fitness – their blood oxygen levels were still impaired, but their levels of a certain neurotransmitter were reduced, lowering their pain threshold. So the result is therefore not only psychological but physiological. I wonder how much of this would transfer into relevant practice for physiotherapists…

    • Hi Alex
      I watched that documentary and it was interesting to see physiological changes driven by psychological mechanisms, do these occur in physiotherapy, well simply put I don’t know, I remember an article about visualisation of an exercise did create a physiological effect, but is this meaningful, would this add significantly to outcome, again I don’t know, but I would doubt it
      Thanks for your comments

  2. That’s amazing that you posted this today, as myself and 2 colleagues had this exact discussion at a cpd meeting yesterday!We all agreed that we simply didn’t feel comfortable making any promises which we didn’t know to be evidence – based and true…..however we also mentioned how frustrating it is when *less qualified* practitioners down the road tell their patients they are ‘popping their pelvis back in’ and suggest they keep coming back to see them any time they feel pain and it’s’going back out again’ for a repeat treatment – and charge even more than a chartered physiotherapist! Their patients are delighted with them and their business is thriving…..
    Would an acceptable approach be to give open, honest explanations like you gave examples of, but follow these with some ‘suggestions’ as to how it may work, and why they may feel better afterwards….? Is utilising the power of suggestion unethical when you’ve preceeded it with an honest review of the current literature?!

    • Hi Caroline
      Thanks for your comments, should we use the power of persuasion in Physio, well I think we do a lot anyway, persuading patients to do their rehab and keep up with their programs, but using persuasion to convince someone something will have an effect that we just don’t know, then I say no!

  3. PS – just came across your blog last week and I’m working my way through every post – love your work! Thanks for taking the time to write it all. I’m interested to know if you use dry needling in your practice, what you think of local twitch responses and referral of symptoms while needling, and if you draw a clear distinction between DN and acupuncture, as I was taught…? Perhaps another blog post on that topic sometime….?!

    • Hi Caroline
      Many thanks for your kind comments, I have been trained in both DN and acupuncture many years ago and I don’t use either anymore, due to my experience and education around the implausibility of the proposed mechanisms, if u read my blog on diagnostic palpation I discuss trigger points a little in there, maybe for another post in the future

  4. Well timed blog, agree with much you have said. I am in the middle of interesting book that came out this April ‘You are the placebo’, mentions about history and various studies about the placebo effect if your interested about it (not sure what the other half is like as yet to finish but interesting so far). Apparently some studies show that even when a person was told they were taking a sugar pill it still produced a positive effect. So guess you do not need to lie, mislead your patients to still get a benefit from the placebo!

    • Thanks for the tip Dave, may have a look at the book! Its an interesting point does the placebo effect occur in some no matter what you say/do is their ingrained beliefs and expectations so strong to over ride what’s presented to them that contradicts them
      Interesting points thanks

  5. I find this very interesting!! lately I have been doubting/questioning if everything we do could be largely placebo, and have noticed improvements/decline in conditions depending on my “delivery” of the treatment. I agree 100% about informed consent on not “up” playing treatments just so they will work.

  6. Hi Adam.
    I must say the placebo effect is fascinating. Just wondering how much information you feel we are duty bound to give the patient. For instance with regard to your manual therapy example do you feel it would be acceptable to omit the first section and simply say “current evidence suggests that any effects you feel will be likely down to neuro-modulation and I may have to try some different ways of doing it!” ?
    I also think that informing the patient and admitting to the short term effects (if any) of some hands on treatments can help to encourage compliance to an exercise program by explaining the difference between symptom relief and actual potential change of the underlying structures/pathology. That is of course if the evidence suggests this will occur!

    • Hi Tighearnach
      This is a debate I have regularly do we need to tell a patient that doesn’t ask that we don’t know what the effects are of a treatment as the evidence is inconclusive?
      I say yes we should, as mentioned giving a patient as much information as we can allows them to make an informed decision.
      I agree that if a patient is aware that manual therapy, or any other passive Rx, is only short term effect it can emphasis the need for long term solution through exercise behaviour change etc.
      Thanks for your comments

  7. Hi, I’m a young pt, will be graduated in september and I really like your blog and twitter. Your article makes me asking a lots of question about how treat and share my knowledge with my patient. All your articles and critices about the placebo effet of physiotape, US or manual therapy … are really confusing for me because this is what I learned at school and how a lot of pt are working nowdays. But thank you to give some reflexion too my mind and my practice.

  8. A great thought provoking read!
    I am a recent grad pt working half private half public in rural NSW, Australia. Particularly within the private domain I constantly find myself being challenged and influenced by patients expectations with regards to treatment “My pelvis is out again and re-aligning it is the only way I can get relief”. I will often try to offer an evidence based explanation for my choice of performing- or not performing a given treatment, only to get a blank look that basically says “less chat,chat more crack,crack”. If I push the explanation line too hard with these people they simply don’t come back, hopefully they go to someone else who offers EBP and they live happily ever after- optimistic right? My solution to this problem thus far has been to meet patients at their beliefs/ expectations then gradually “drip feed” bits of information and other treatment to slowly influence some conceptual change.
    My questions is; have you encountered similar firmly held expectations and how do you deal with them?

    • Hi Jack
      First of all apologies for not replying sooner, your comment got lost and I’ve only just stumbled across it
      To answer simply, yes I’ve experienced exactly similar situations and dealt with them pretty much the same as you have! Going and telling a patient that this crack crack crack isn’t really helping won’t get you far, as you said slow drop feeding and slipping in subtle education as you crack crack a few times and then try and see how it goes to ween them of the manual therapy and start the self management and exercise route

  9. Stumbled on your blog a week ago and could have contributed to pretty much all posts as i work through them. My experience as a physio is similar to your story. I took it pretty hard when i realised most of what i’d been taught and practicing didn’t fit the condition/person. The most eye opening book was Daniel Kahneman- Thinking fast and slow. Not necessarily that it said brand new things but it allowed me to see my own bias in a way that was a little upsetting! (don’t worry I’m ok now- I think!) What we see is not all there is!
    I laughed out loud at the activated bullshit cos the lunch break of the first day i attended I said to my girlfriend they are either a genius or full of shit! Unfortunately they were full of shit with a fat wallet. Smoke and mirrors! The only money I’ve spent on education since is books. If people are gonna make this shit up then I may as well do the reading and make it up myself!
    Anyway the placebo effect for me is quite simple (as it has to be for me to be consistent) and it all comes down to whether we intentionally intend to deceive. Non specific effects can come from anything and as long as we are spreading evidence based truth, which includes allowing ourselves to say to people we don’t know, then i think we can use the kitchen sink if we want.
    The problem with placebo effect spread through deception in my opinion is that even if it works brilliantly this time if it doesn’t work next time we may have created an anxiety that for all we know could create a bigger problem than the original one we helped resolve.
    Well done for the blog Adam, Its another one of the things that helps me keep fumbling on in the dark.

    • Hi Neil
      Thanks for your comments, I do like to hear of others frustrations with this profession, as at times with all the backlash I get for speaking out I do wonder if I’m in a minority
      You make a great and valid point about placebo, deliberate deception is unethical and immoral and removes informed conset, and as you said placebo effects are unreliable so if it doesn’t work when it did before it can have more detrimental effects than positive ones
      Thanks again

  10. Hi Adam,
    First I’d like to preface this by saying I am a large fan of your blog and it has encouraged me to be much more scrutinous in my own studies at school.
    My main question would be if someone came in with some sort of pain, and requested k-tape application because they have had it in the past and they felt it relieved some of their symptoms.
    Do you send em packing saying that you don’t believe in k-tape because studies say it is mainly a placebo effect? Do you clearly state it is a placebo and tell them so? (Possibly lessening their belief in its efficacy and thereby lessening the benefit of it) Or is your main gripe with the therapists who perpetuate the myth that is a valid way of treating someone? Or am I completely missing the boat here?
    I know a 700 pound deadlifter who won’t train without a couple strips on his lumbar paraspinals, two strips of tape can’t possible exert enough force to do anything to help pull that kind of weight, but if you told him that, he might stop believing in them and lose his “mental edge”.
    Thank you for your time, it helps provide some clarity when I have many folks around campus espousing the benefits of product ‘x’ or technique ‘y’.

    • Hi Adam (great name by the way)
      Thanks for your kind and interesting comments
      So to start with I will say yes we have to manage our patients expectations, but I will always explain any treatment or modality the best I can with my understanding of the current evidence base and my knowledge of it. So for K tape and other such stuff I will often say something like we don’t know its true effects there is a big element of placebo etc etc…
      In my opinion we should never dupe or be deceitful in explanations to patients just to get a placebo effect, if this has a negative effect on the placebo then so be it!
      The patient always needs to make an informed decision and so we must present the evidence and facts, if a patient has a ritual or belief and there is no risk or harm because of that eg tape or belt then let them carry on, if a patient wants to continue with an ineffective treatment after my explanation and recommendation that they don’t or try an alternative then, i respectfully suggest they try elsewhere, after I have had another go to to show them the alternatives or better option.
      Hope that clears things up

  11. Good commentary Adam 🙂
    In the case above the dead lifter would probably go elsewhere, the power of placebo is
    1. Large
    2. Long lasting ( especially if enforced by + ve patient experience )
    So while explaining the evidence ( which in itself is not easy to all patients ) is integral to practice sometimes a judgement call has to be made.
    The effect of placebo will not diminish or disappear in yrs to come it will only become easier to understand and explain.
    Zhang W, Robertson J, Jones AC, Dieppe PA, Doherty M. The placebo effect and its determinants in osteoarthritis: meta-analysis of randomized controlled trials. Ann Rheum Dis. 2008 Dec;67(12):1716-23.
    Nickel JC, Fradet Y, Boake RC, Pommerville PJ, Perreault JP, Afridi SK, Elhilali MM. Efficacy and safety of finasteride therapy for benign prostatic hyperplasia: results of a 2-year randomized controlled trial (the PROSPECT study). CMAJ. 1996 Nov 1;155(9):1251-9.

  12. Always an interesting read Adam!
    I have previously chatted to you very briefly via Twitter on this subject. Personally I don’t see any issue in us maybe eliciting a placebo effect. I do agree that it is wrong to outright lie and deceive patients, that isn’t up for debate.
    But I had a great example as a student once. Saw a lady with subacromial pain once who was really lacking QoL because of the reduced movement and pain in her shoulder, she was at her wits end bless her. Gave her the relevant exercises, followed evidence base where I could, discussed it with my Band 7 educator who agreed with everything I had done. Left her a few weeks and re-Ax her to find all her objective markers were EXACTLY the same but she reported she felt great and the scapula setting exercise (which we all now know isn’t very useful) was great! I had the dilemma for around 4-5 weeks whereby every time I saw her she was objectively pretty much the same but emotionally and psychologically said she felt so much better and couldn’t thank me enough.
    In the end she felt she didn’t need any physio anymore cause she was coping well, I left my placement but did not discharge her because it felt a bit wrong haha.
    Now I’m a lot busier, more patient centred and cynical as well as understanding towards the psychology of pain I’d probably just go with her wishes and discharge her. Where do you stand on things like that?
    Thanks as always!

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