Intended for healthcare professionals


Components of placebo effect: randomised controlled trial in patients with irritable bowel syndrome

BMJ 2008; 336 doi: (Published 01 May 2008) Cite this as: BMJ 2008;336:999

Let us call it “Curabo effect”

In their study on components of placebo effects (1), Kaptchuk et al. found that the most robust component of placebo is the patient-physician relationship. Not any patient-physician relationship, of course, but a relationship with definite qualities: “Warmth, empathy, duration of interaction and communication of positive expectation”. Positive expectations, whether communicated to the patient or not, seem to have an independent effect (2,3) and might be especially potent when they are rooted in the doctor’s confidence in the prescribed treatment (4).

The correlation between doctor’s positive expectation and patient progress might indeed be significant enough to deserve a name of its own: The “I-will-cure-this-patient” attitude or, closer to the linguistic rationale of the word placebo: the “curabo effect” (“curabo” means “I will cure” in latin, while “placebo” means “I will please”).

In research conditions, when treatment is given with doubts that it might be only a placebo, the “curabo effect” may be non-operative and non -apparent because it is evenly distributed in the study groups. On the contrary, in the real world practice, when the prescriber is honestly convinced of giving a “verum” treatment with specific effectiveness, the “curabo effect” can develop its full potential.


(1) Kaptchuk TJ, Kelley JM, Conboy LA, Davis RB, Kerr CE, Jacobson EE, et al. Components of placebo effect: randomised controlled trial in patients with irritable bowel syndrome. BMJ 2008; doi: 10.1136/bmj.39524.439618.25

(2) Priebe S, Gruyters T. The importance of the first three days: predictors of treatment outcome in depressed in-patients. Br J Clin Psychol 1995;34(pt 2):229 –36.

(3) Clarkin JF, Hurt SW, Crilly JL. Therapeutic alliance and hospital treatment outcome. Hosp Community Psychiatry 1987;38:871–5.

(4) Graz B, Wietlisbach V, Porchet F, Vader JP: Prognosis or “Curabo Effect?” Physician Prediction and Patient Outcome of Surgery for Low Back Pain and Sciatica. Spine 2005;30 (12):1448–1452.

Competing interests: None declared

Competing interests: No competing interests

15 April 2008
Bertrand Graz
research fellow
John-Paul Vader
University Institute for Social and Preventive Medicine, Bugnon 17, 1005 Lausanne, Switzerland