title: [The placebo effect: is the wish father to the thought?].
abstract: The placebo effect remains an interesting topic for research. Recently, a systematic review estimated the percentage of responders after various placebo interventions in studies assessing prophylactic treatment for migraine. The authors report that after oral, pharmacologic placebos, 22% of patients reported an attack frequency reduction of > 50% and that after sham acupuncture, this percentage was 38%. In this commentary the methodological issues of the paper are discussed, and the conclusion is that in research into placebo effects the wish might be father to the thought.
authors.affiliation: Leids Universitair Medisch Centrum, afd. Ouderengeneeskunde, Leiden.
authors.forename: A J M Ton
authors.initials: AJ
authors.lastname: de Craen
mesh_terms: D015982:Bias; D019317:Evidence-Based Medicine; D006801:Humans; D015990:Placebo Effect; D015983:Selection Bias