[Predictors of resource use in inpatient psychotherapy: development of a German case group concept for patients with mental disorders].

Objective: Recent research on predictors of resource use in inpatient psychotherapy indicates that various patient characteristics as well as therapeutic factors may influence resource use. The aim of our study was to examine the relationship between patient attributes and psychotherapeutic costs in German inpatient psychotherapy. The amount of variance explained in resource use was calculated.

Method: The existing sample used in this study consists of sociodemographic and clinical variables of 2375 patients treated in various inpatient psychosomatic clinics. Resource use was measured on the basis of clinical staff activities (Klassifikation Therapeutischer Leistungen, KTL, BfA 2000). Regression Tree Analysis was performed to classify patient attributes based on resource use.

Results: The model assigns patients to 20 classes, accounting for 17.5 % of variance. Those patients with single status and personality or eating disorder consume more resources than those patients with non-single status, low motivation for psychotherapy, comorbidity of physical illness and lower levels on symptom severity.

Conclusions: Implications of the results for the development of a patient classification system in inpatient psychotherapy will be discussed.