Placebo effect : fact or fiction?

For over 40 years since the moment when H.K. Beecher published The powerful placebo in 1955, it has been universally accepted that the placebo effect is a fact and it is very powerful. At the turn of the 20th and 21st centuries the papers expressing doubts concerning the existence and power of the placebo effect were published. They started a debate about the existence and the power of the placebo effect. The aim of this paper is to review and sum up the debate which has been carried on for 10 years among placebo researchers and to find an answer to the question whether the placebo effect exists and if so whether it is powerful enough to be of any clinical significance.