Transference interpretation and psychotherapy outcome: a systematic review of a no-consensus relationship

Despite its well-established importance in psychoanalytic theory, there is a scarcity of empirical evidence on the relationship between a therapist's transference interpretation (TI) and therapeutic outcome. The current scientific literature shows no consensus on the existence and nature of such an association. Therefore, the present study aimed to systematically review the literature on the link between TI and outcomes in psychodynamic psychotherapies. The American Psychological Association PsycInfo, MEDLINE, and the Web of Science Core Collection were selected as the primary databases for the literature search. Studies were included if they measured the frequency/ concentration of TI in psychodynamic psychotherapy [e.g., transference focused psychotherapy (TFP), supportive-expressive therapy] or compared a treatment group (e.g., high in TI and TFP) with a control group (e.g., low in TI supportive therapy) in an adult population with psychiatric symptoms. Out of 825 retrieved abstracts, 25 articles (21 studies) were included in the final synthesis. 13 out of 21 (62%) studies showed a significant improvement in at least one therapy outcome measure following the use of TI. The present systematic review also revealed high heterogeneity across studies in terms of TI measurement, outcome assessment (e.g., psychiatric symptoms, dynamic change, interpersonal functioning, therapeutic alliance), study design (e.g., experimental, quasi-experimental, naturalistic), patient population (e.g., anxiety disorders, personality disorders), and types of treatment (e.g., TFP, supportive-expressive therapy), preventing researchers from asserting solid conclusions. The results strongly highlight the urgent need for highquality research to understand which types of patients, how, and when TIs could be effective throughout the therapy process.