title: The variables problem and progress in psychotherapy research.
abstract: In this journal's first article, Strupp (1963) pointed to problems specifying independent and dependent variables as a source of slow progress in psychotherapy outcome research. This commentary agrees, shows how the concept of variable loses its meaning in psychotherapy research because of participants' responsiveness, and notes an alternative research strategy that does not depend on variables.
authors.forename: William B
authors.identifier: 0000-0001-7740-0609
authors.initials: WB
authors.lastname: Stiles
mesh_terms: D006801:Humans; D010043:Outcome and Process Assessment, Health Care / Q000266:history*; D011613:Psychotherapy / Q000266:history*