Evaluating the Psychometric Properties of the German Adaptation of the Client Attachment to Therapist Scale

Background The present study examines the psychometric properties of the German adaptation of the Client Attachment to Therapist Scale (CATS). The validity of the scale as originally proposed has recently been brought into question, as patients were identified as “pseudosecure”. Methods We examined the measure’s factorial structure, as well as reliability and validity towards related measures using a clinical sample of N = 354 participants. Results We found the original model, consisting of 36 items to be lacking in terms of model fit and construct validity. A shortened 12-item version exhibited markedly improved model fit and reliability. Correlations to related constructs demonstrated that none of the scale’s validity was lost by shortening it. Furthermore, we showed scalar invariance across groups of age and sex. Conclusions The shortened CATS-S can be recommended for future use in clinical research in German-speaking populations as a valid, reliable, and economical alternative to the longer version.