title: Investigating placebo effects in irritable bowel syndrome: a novel research design.
abstract: Little is known about placebo effects with scientific precision. Poor methodology has confounded our understanding of the magnitude and even the existence of the placebo effect. Investigating placebo effects presents special research challenges including: the design of appropriate controls for studying placebo effects including separating such effects from natural history and regression to the mean, the need for large sample sizes to capture expected small effects, and the need to understand such potential effects from a patient's perspective. This article summarizes the methodology of an ongoing NIH-funded randomized controlled trial aimed at investigating whether the placebo effect in irritable bowel syndrome (IBS) exists and whether the magnitude of such an effect can be manipulated to vary in a manner analogous to "dose dependence." The trial also uses an innovative combination of quantitative and qualitative methods.
authors.affiliation: Osher Institute, Division for Research and Education in Complementary and Integrative Therapies, Harvard Medical School, 401 Park Drive, Suite 22A, Boston, MA 02115, USA.
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Conboy
authors.forename: Rachel H
authors.initials: RH
authors.lastname: Wasserman
authors.forename: Eric E
authors.initials: EE
authors.lastname: Jacobson
authors.forename: Roger B
authors.initials: RB
authors.lastname: Davis
authors.forename: Anna T R
authors.initials: AT
authors.lastname: Legedza
authors.forename: Min
authors.initials: M
authors.lastname: Park
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Rivers
authors.forename: Elizabeth B
authors.initials: EB
authors.lastname: Morey
authors.forename: Bong Hyun
authors.initials: BH
authors.lastname: Nam
authors.forename: Louis
authors.initials: L
authors.lastname: Lasagna
authors.forename: Irving
authors.initials: I
authors.lastname: Kirsch
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Lembo
authors.forename: Ted J
authors.initials: TJ
authors.lastname: Kaptchuk
authors.forename: Catherine E
authors.initials: CE
authors.lastname: Kerr
mesh_terms: D015670:Acupuncture Therapy; D003627:Data Interpretation, Statistical; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000628:therapy*; D010817:Physician-Patient Relations; D015990:Placebo Effect; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D011795:Surveys and Questionnaires