title: Assessing clinical significance of treatment outcomes using the DASS-21.
abstract: Standard clinical significance classifications are based on movement between the "dysfunctional" and "functional" distributions; however, this dichotomy ignores heterogeneity within the "dysfunctional" population. Based on the methodology described by Tingey, Lambert, Burlingame, and Hansen (1996), the present study sought to present a 3-distribution clinical significance model for the 21-item version of the Depression Anxiety Stress Scales (DASS-21; P. F. Lovibond & Lovibond, 1995) using data from a normative sample (n = 2,914), an outpatient sample (n = 1,000), and an inpatient sample (n = 3,964). DASS-21 scores were collected at pre- and post-treatment for both clinical samples, and patients were classified into 1 of 5 categories based on whether they had made a reliable change and whether they had moved into a different functional range. Evidence supported the validity of the 3-distribution model for the DASS-21, since inpatients who were classified as making a clinically significant change showed lower symptom severity, higher perceived quality of life, and higher clinician-rated functioning than those who did not make a clinically significant change. Importantly, results suggest that the new category of recovering is an intermediate point between recovered and making no clinically significant change. Inpatients and outpatients have different treatment goals and therefore use of the concept of clinical significance needs to acknowledge differences in what constitutes a meaningful change.
authors.affiliation: School of Psychology, The University of Western Australia.
authors.forename: Fiona R
authors.initials: FR
authors.lastname: Ronk
authors.forename: James R
authors.initials: JR
authors.lastname: Korman
authors.forename: Geoffrey R
authors.initials: GR
authors.lastname: Hooke
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Page
mesh_terms: D000275:Adjustment Disorders / Q000175:diagnosis / Q000523:psychology / Q000628:therapy; D000293:Adolescent; D000328:Adult; D000368:Aged; D000553:Ambulatory Care; D001008:Anxiety Disorders / Q000175:diagnosis / Q000523:psychology / Q000628:therapy; D001521:Behavior Therapy; D015928:Cognitive Behavioral Therapy; D003431:Cross-Cultural Comparison; D003866:Depressive Disorder / Q000175:diagnosis / Q000523:psychology* / Q000628:therapy*; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000523:psychology / Q000628:therapy*; D008875:Middle Aged; D019964:Mood Disorders / Q000175:diagnosis / Q000523:psychology / Q000628:therapy; D010043:Outcome and Process Assessment, Health Care / Q000706:statistics & numerical data; D010554:Personality Disorders / Q000175:diagnosis / Q000523:psychology / Q000628:therapy; D010555:Personality Inventory / Q000706:statistics & numerical data*; D011594:Psychometrics; D011615:Psychotherapy, Group; D011618:Psychotic Disorders / Q000175:diagnosis / Q000523:psychology / Q000628:therapy; D011788:Quality of Life / Q000523:psychology; D012016:Reference Values; D015203:Reproducibility of Results; D019966:Substance-Related Disorders / Q000175:diagnosis / Q000523:psychology / Q000628:therapy; D014481:United States; D014904:Western Australia; D055815:Young Adult