The clinical psychological diagnostic system (KPD-38): sensitivity to change and validity of a self-report instrument for outcome monitoring and quality assurance.
BACKGROUND
Monitoring psychotherapeutic progress requires valid and economic measures to detect change of clinical relevance. We addressed validity and sensitivity to change of the 'Klinisch Psychologisches Diagnosesystem 38' (KPD-38, Clinical Psychological Diagnosis System), an instrument for outcome monitoring and quality assurance.


METHODS
Data from an inpatient sample (n = 1.377) were used to investigate the concurrent validity, the sensitivity to change, and the criterion validity of the KPD-38 in comparison to the Outcome Questionnaire (OQ-45) and the Brief Symptom Inventory (BSI).


RESULTS
Sensitivity-specificity analyses showed similar sensitivity and higher specificity for the KPD-38 scales compared with the BSI and OQ total scores. Change rates on the KPD-38 distress scale (DIS) were found to be lower than on the BSI (KPD-38 DIS: 36.6%, GSI: 67.7%) and the OQ-45 (KPD-38 DIS: 44.3%, OQ tot: 57.1%) total scores. Concordance was low with the BSI ([κ = 0.24] and moderate with the OQ-45 [κ = 0.45]).


CONCLUSIONS
Implications for applications in the field of outcome assessment and the challenge of further validation are discussed. The relation between sensitivity to change and criterion validity is highlighted.
Moessner
Markus
M
University Hospital Heidelberg, Center for Psychotherapy Research, Heidelberg, Germany. moessner@psyres.de
Gallas
Christine
C
Haug
Severin
S
Kordy
Hand
H
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007297:Inpatients / Q000523:psychology / Q000706:statistics & numerical data; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis* / Q000523:psychology / Q000628:therapy*; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics; D011785:Quality Assurance, Health Care / Q000592:standards*; D011786:Quality Control; D015203:Reproducibility of Results; D057566:Self Report / Q000592:standards*; D012680:Sensitivity and Specificity; D055815:Young Adult