title: What is controlled for in placebo-controlled trials?
authors.forename: Roger B
authors.initials: RB
authors.lastname: Fillingim
authors.forename: Donald D
authors.initials: DD
authors.lastname: Price
mesh_terms: D035061:Control Groups; D018849:Controlled Clinical Trials as Topic / Q000523:psychology*; D006801:Humans; D010146:Pain / Q000523:psychology; D059408:Pain Management; D015990:Placebo Effect; D010919:Placebos
chemical_list: D010919:Placebos