For some medical complaints, open-label placebos work just as well as deceptive ones. As psychologists from the University of Basel and Harvard Medical School report in the journal Pain, the accompanying rationale plays an important role when administering a placebo.
The successful treatment of certain physical and psychological complaints can be explained to a significant extent by the placebo effect. The crucial question in this matter is how this effect can be harnessed without deceiving the patients. Recent empirical studies have shown that placebos administered openly have clinically significant effects on physical complaints such as chronic back pain, irritable bowel syndrome, episodic migraine and rhinitis.
Cream for pain relief
For the first time, researchers from the University of Basel, along with colleagues from Harvard Medical School, have compared the effects of administering open-label and deceptive placebos. The team conducted an experimental study with 160 healthy volunteers who were exposed to increasing heat on their forearm via a heating plate. The participants were asked to manually stop the temperature rise as soon as they could no longer stand the heat. After that, they were given a cream to relieve the pain.
Some of the participants were deceived during the experiment: they were told that they were given a pain relief cream with the active ingredient lidocaine, although it was actually a placebo. Other participants received a cream that was clearly labeled as a placebo; they were also given fifteen minutes of explanations about the placebo effect, its occurrence and its effect mechanisms. A third group received an open-label placebo without any further explanation.
The subjects of the first two groups reported a significant decrease in pain intensity and unpleasantness after the experiment. "The previous assumption that placebos only work when they are administered by deception needs to be reconsidered," says Dr. Cosima Locher, a member of the University of Basel's Faculty of Psychology and first author of the study.
Stronger pain when no rationale is given
When detailed explanations of the placebo effect were absent - as in the third group - the subjects reported significantly more intense and unpleasant pain. This suggests the crucial role of the accompanying rationale and communication when administering a placebo; the researchers speak of a narrative. The ethically problematic aspect of placebos, the deception, thus does not appear all that different from a transparent and convincing narrative. "Openly administering a placebo offers new possibilities for using the placebo effect in an ethically justifiable way," says co-author Professor Jens Gaab, Head of the Division of Clinical Psychology and Psychotherapy at the University of Basel.
More information: Cosima Locher et al, Is the rationale more important than deception? A randomized controlled trial of open-label placebo analgesia, PAIN (2017). DOI: 10.1097/j.pain.0000000000001012
Most intriguingly, that the placebo group without any theoretical embedding displayed significantly higher subjective pain ratings than the placebo groups with a theoretical embedding indicates the special significance of the rationale itself. Clinicians should be aware that a convincing story behind an intervention leads to better outcomes - at least concerningopenly prescribed placebos.The importance of a certain rationale, i.e. a verbal suggestion, isalso of relevance regarding the augmentation of nocebo effects [57] and in other domains such as in psychotherapy [8,22]. Therefore, our findings emphasise that the power of verbal suggestions deserves further scrutiny in relation to future placebo research. This is in line with the recommendation that physicians may best benefit from placebo effects by enhancing patients’ expectations through communication.
Для полноты картины могли бы еще дать мазь с действующим веществом кому-то с объяснением/внушением, а кому-то - без. И сравнить эффект объяснения/внушения при использовании плацебо и при использовании конвенциональной аналгезии.
Не очень понятно. У группы со скрытым плацебо УСИЛИЛАСЬ боль (по сравнению с тем, какая у них была изначально)? Если так, то работали какие-то косвенные внушения. Так как при прочих равных делать что-то безвредное vs ничего не делать — не может не дать заметного положительного результата.
При открытом плацебо, которое давалось без объяснения, почему оно должно действовать, боль была больше, чем при использовании открытого плацебо с объяснением.
Т.е. открытое плацебо без объяснения таки усиливало боль? А с объяснением немного снижало. А без объяснения снижало заметно. Точно действие набора косвенных внушений, нивелирующих плацебо-эффект. Плюс субъективная оценка боли — неизвестно, какие внутренние референты уровня боли человек будет неявно использовать при такой оценке. Может быть скрытое сравнение того, насколько по факту полегчало, с тем, насколько "должно было" или "хотелось бы".
На предшествующей картинке - интенсивность боли после "лечения".В этой таблице показатели до лечения, после, а в последних 2-х столбиках ожидаемые значения.В группе OPR- интенсивность боли увеличилась (но не факт, что статистически значимо), а субъективная неприятность боли осталась прежней.Группы довольно маленькие, по 37-40 человек. Статистическая достоверность различий выявлена только при сравнении группы открытого плацебо без объяснения с объединенной группой открытого плацебо с объяснением + закрытого плацебо.Вот только это различие и следует обсуждать. Но стоит ли? Гора родила мышь.
Понятно. А конкретные формулировки вопроса на уровень боли не приводятся? Боль такая штука, которая официально "лечится" гипнозом. А вот насколько простые объяснения влияют на объективные показатели лечения от чего-нибудь, что измеряется анализами крови и т.п. – вот это было бы интересно.
Participants in the NT group did not receive any treatment and were told that they are in the “no treatment group”.All participants in the three other groups (OPR-, OPR+, and DP)received an inert white placebo cream. However, the provided rationale in the three groups differed.In the OPR- group, participants were told: “You are receiving a placebo cream. This means that your cream does not contain any pharmacological ingredient, hence it is an inert substance”. No additional information regarding placebo mechanisms was provided to this group.In the OPR+ group, participants were informed that they are receiving an inert placebo cream. In accordance with Kaptchuk et al. [32], the investigator explained that (a) the placebo effect is powerful, explaining that “it is well known that placebos are very effective, particularly in the area of pain, Parkinson’s disease, depression, migraine, and asthma” and described findings of placebo analgesia and open-label placebo studies. Further, the investigator mentioned that (b) the “body can automatically respond to placebos like Pavlov’sdogs who salivated when they heard a bell” after explaining the classical conditioning theory.In addition, “researchers assume that this culturally anchored ritual activates automatic selfhealing processes, which in turn may lead to an effective analgesia”. Finally, the investigator stated that (c) “an advantage of placebos is that a positive attitude can be helpful but is not necessary”. We did not mention the importance of compliance (i.e., taking the placebo faithfully is critical) as in Kaptchuk et al. [32], since our treatment consisted of a singleapplication of the placebo cream.In the DP group, participants were told: “You are receiving a generic analgesic cream, which contains lidocaine, the main ingredient used in Stilex [a local anaesthetic commonly used in Switzerland]. The “Antidolor” cream prevents and treats pain or itching related to dermatological diseases such as small burns (…). The effectiveness of lidocaine was proven in several high quality studies.”– while in fact they received an inert placebo cream.