[Psychic impairment in psychosomatic and psychiatric quality assessment: global assessment of functioning scale (GAF) vs. impairment score (IS)].
OBJECTIVE
The Global Assessment of Functioning Scale (GAF) and the Impairment-Score (IS) are important instruments for Quality Assessment. There are only few studies examining the quality of statistical power of the GAF-Scale indicating problems in construct validity and no larger studies for the IS.


METHODS
For a sample of 263 patients the Psy-BaDo and an OPD-Rating were completed.


RESULTS
Though the distribution of both scales show large range, the proportion of explained variance is 58 %. This proportion can be increased to 68 % for the IS by including the OPD-Ratings. The GAF-Scale in contrast is not associated with the OPD-Ratings.


CONCLUSIONS
The results indicate, that the combination of both scales is necessary to represent the whole variance of psychic impairment (ICD-10 Chapter F & Z). In addition the valid rating of both scales is very difficult for patients with somatic disorders and somato-psychic problems.
Klinik und Poliklinik für Psychosomatik und Psychotherapie, Universitätsklinikum Münster, Domagkstr. 22, D-48149 Münster, Germany. langeco@mednet.uni-muenster.de
Corinna
C
Lange
Gereon
G
Heuft
D000203:Activities of Daily Living / Q000523:psychology; D006801:Humans; D010555:Personality Inventory / Q000706:statistics & numerical data*; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D011594:Psychometrics; D011602:Psychophysiologic Disorders / Q000175:diagnosis / Q000523:psychology*; D011788:Quality of Life / Q000523:psychology*; D015203:Reproducibility of Results; D012803:Sick Role; D013001:Somatoform Disorders / Q000175:diagnosis / Q000523:psychology*