What's wrong with the placebo effect?

Reader sprachen sie singlish, commenting on this previous post, wrote:


Never figured out why the Placebo had such bad rep.

Statistically significant improvement for the patient, no side effects. What more could your ask for when apply the Harm Principal?


What's wrong, indeed, with the placebo effect?

(Or more appropriately, with "placebo effects", since it is an umbrella term that covers a number of mechanisms which might affect a patient's physiology or how he perceives his symptoms.)

It is a commonly posed question and a common defence used by proponents of alternative medicine when evidence shows that their favoured modality of treatment is no better than placebo, and that any beneficial effect observed as a result of that therapy is therefore also likely due to the placebo effect.

Because it is a commonly posed question and a commonly used defence, it is a question that has been answered many times by science and medical writers and bloggers. angry doc does not claim to be able to answer the question comprehensively or in depth, but he will do the best he can, with regards to the study in question.

First of all, the improvement observed in the study is not large enough to be considered clinically significant.

That aside, it is also worth noting that while the parents and clinicians all reported improvement in their scores, scores given by the subjects themselves were a more mixed result - some subjects reported improvement in certain domains but felt they did worse in other domains. In other words, the observers thought that the subjects were functioning better, regardless or whether or not the subjects themselves were feeling better - the placebo effect affects the observers, and not the subjects! This of course has ethical implication when it comes to using a treatment on subjects who cannot communicate how they are feeling - patients such as infants, children, those who are mentally-impaired, and even pets; we can think that we are helping them, when in fact we may be doing nothing, or indeed harm to them.

Also, it is not true that there are no side effects with placebos or biologically non-active agents. Patients given non-active agents can in fact develop adverse effect to them, as was the case with one patient in this study, who had to drop out of the study. This is known as the nocebo effect. Placebos, because we do not always know the precise mechanism by which they work, are often unpredictable in their effect, and can in fact have the reverse effect from that which is desired.

Finally, even if we take the result of this study to mean that placebos are effective for ADHD in children and adolescent, the question of what to give the patients remain: do you give them "a mixture of rice protein powder and a small amount of activated charcoal" or "0.3% hypericin... free of heavy metals, pesticides, and adulterants"? Or something else which has already been proven to be more effective than placebo for ADHD?

If you choose to give a patient a placebo, do you tell him you are giving him a placebo, or do you lie to him and tell him you are giving him "something that works"? Do you want to lie to your patient? Would you want your doctor to lie to you?

The fact is there are practitioners out there who are prescribing treatment to patients which have been shown to be no superior to placebo. If indeed all that they are giving is the placebo effect, then does it justify the cost to the patients? Does it justify the practitioner's time learning all he learnt? Does it not make the whole practice dishonest?

Having said that, all 'healers' use the placebo effect to a degree in his or her practice. The simple ritual of a consultation is sometimes all it takes to make the patient feel better. It is probably impossible to quantify or eliminate such effects from our practice, but angry doc feels that where we know that a treatment is no better than placebo, it is detrimental to the patient-doctor relationship to prescribe it as "something which works", or to not resort to something which has indeed been proven to work.