title: Signal and noise in psychotherapy. The role and control of non-specific factors.
abstract: Four major categories of non-specific or common factors are systematically analysed: relationship, expectancy, reorganising, and impact factors. The placebo control method should be discarded in psychotherapy research for two reasons: (a) sham treatment controls are unworkable because common factors in treatment are manifest only when real treatment is administered; and (b) the very events which were once thought of as 'non-specific' noise are now recognised as active therapeutic factors common to many schools.
authors.affiliation: Harvard University Graduate School of Education, Program in Counselling and Consulting Psychology, Cambridge, Massachusetts 02138.
authors.forename: H
authors.initials: H
authors.lastname: Omer
authors.forename: P
authors.initials: P
authors.lastname: London
mesh_terms: D000223:Adaptation, Psychological; D005500:Follow-Up Studies; D006801:Humans; D001523:Mental Disorders / Q000628:therapy*; D010817:Physician-Patient Relations; D011613:Psychotherapy / Q000379:methods*; D012718:Set, Psychology