Focusing on the adult attachment style in schizophrenia in community mental health centres: Validation of the Psychosis Attachment Measure (PAM) in a German-speaking sample

Background: Assessing attachment style in people with schizophrenia may be important to identify a risk factor in building a strong therapeutic relationship and so indirectly to understand the development of mal-compliance as one of the major obstacles in the treatment of schizophrenia. Aims: The present study analysed the psychometric properties of the German version of the Psychosis Attachment Measure (PAM), which assesses avoidant and anxious attachment style. Methods: A sample of 127 patients suffering from chronic schizophrenia or schizoaffective disorder participated in this study. In testing discriminant validity, we assessed psychopathology, depression, therapeutic relationship and service engagement. Internal consistency, test-retest reliability and factor structure were analysed. Results: The German version of PAM exhibited acceptable to good internal and test-retest reliabilities and the two-factor structure of the English version could be replicated. Avoidant attachment style was related to higher levels of positive symptoms and to a poorer therapeutic relationship. In the context of external validation, a regression analysis revealed that a poor therapeutic relationship correlated with avoidant attachment style, independent of anxious attachment style and depressive symptoms. Anxious attachment was associated with higher treatment adherence. Both insecure attachment styles (avoidant and anxious) were found to be correlated with higher levels of depression, but only attachment anxiety had an independent predictive value for self-reported depression in regression analysis. Conclusions: The German version of PAM displayed satisfactory psychometric properties and seems to be a reliable measure for assessing attachment style in individuals with schizophrenia. Validation of PAM led to the finding that only the avoidant attachment style might be a risk factor when building a strong therapeutic relationship in schizophrenia. In future studies, other factors influencing therapeutic relationship should be taken into account. Anxious attachment style may be a risk factor for depression, but it also has an enhancing effect on treatment adherence.