The German version of the helping alliance questionnaire: psychometric properties in patients with persistent depressive disorder

BACKGROUND: The Helping Alliance Questionnaire (HAQ) is a frequently used and highly relevant instrument to assess the therapeutic alliance. The questionnaire was translated into German by Bassler and colleagues (1995) and is available for patients (HAQ-P) and therapists (HAQ-T). Whereas the HAQ-P has been tested regarding psychometrics, the HAQ-T has not. This study aimed at further investigating the psychometric properties of both the HAQ-P and HAQ-T. We hypothesized that the instrument is reliable and shows factorial as well as convergent validity. METHODS: Within the framework of a multisite, randomized-controlled clinical trial, comparing the efficacy of Cognitive Behavioral Analyses System of Psychotherapy (CBASP) and supportive psychotherapy (SP) in the treatment of early onset persistently depressed outpatients, the HAQ was filled out by patients (n = 255) and therapists (n = 81). 66.0% of patients were female; average age at randomization was 44.9 years (SD = 11.8). Several confirmatory factor analyses were conducted to test different structures for the HAQ. In addition, correlations between the HAQ and the Inventory of Interpersonal Problems (IIP) were calculated to test for convergent validity. RESULTS: Goodness of fit indices for both a model with two different but strongly related factors named ‘relation to the patient/ therapist ’ and ‘satisfaction with therapeutic outcome’ and a second model with only one global helping alliance factor were comparable: Chi-Square-based indices rejected the models; RMSEA closely approached the threshold of good model fit, and CFI/ TLI and SRMR suggested that both models sufficiently fit the data. The internal consistency (Cronbach’s α) calculated for the different scales of the HAQ ranges between questionable to good. Finally, the HAQ scores were significantly related to some of the IIP scores. CONCLUSIONS: The German versions of the HAQ offer sufficient reliable instruments for the quick assessment of different facets of the therapeutic alliance. The HAQ global scores can be used as indicators for the global impression of the patients and therapists perception of the quality of the therapeutic alliance. However, the small correlations found between the IIP and the HAQ puts the question of external validity into perspective. TRIAL REGISTRATION: This study analysed data from a RCT which was registered on ClinicalTrials.com (NCT00970437). First submitted on September 1, 2009.