Psychotherapieforschung und deren Grundlagen bildet den Hauptschwerpunkt der an der IPU angesiedelten Forschungsprojekte. Sie umfasst ein breites Spektrum an Fragestellungen der Klinischen Psychologie, Entwicklungspsychopathologie sowie Psychotherapieoutcome- und -prozessforschung, die in enger Anbindung an die psychotherapeutische Hochschulambulanz (HSA, s. u.) untersucht werden. Die Erforschung ihrer Grundlagen richtet sich auf Risikofaktoren, Entstehung und Verläufe von psychischen Störungen sowie deren Diagnostik. Ebenso werden affektive und kognitive Prozesse untersucht, die Veränderungen im psychotherapeutischen Kontext begleiten können, wobei sowohl behaviorale und beobachtende als auch neurowissenschaftliche Methoden Einsatz finden.

Psychotherapy research and its foundations form the main focus of the research projects based at the IPU. It covers a broad spectrum of issues in clinical psychology, developmental psychopathology and psychotherapy outcome and process research, which are investigated in close cooperation with the psychotherapeutic outpatient clinic (HSA, see below). Research into its foundations focuses on risk factors, the development and progression of mental disorders, and their diagnosis. Affective and cognitive processes that can accompany changes in the psychotherapeutic context are also investigated, using behavioral, observational, and neuroscientific methods.

The central aspect of psychotherapy research at the IPU is the evidence-based application of psychotherapeutic methods, both in settings close to everyday life and in randomized controlled trials for patients of all ages and with a wide range of problems and illnesses relevant to clinical care. These include trauma disorders, affective disorders, obsessive-compulsive disorders, personality disorders, psychoses and anxiety disorders. Within this framework, therapy concepts for these mental disorders are also developed and tested, enabling a close link between university research and clinical practice.
Clinical studies and the preparation of reviews and meta-analyses on the effectiveness of psychotherapy generate results with the highest evidence level within evidence-based medicine, which are incorporated into domestic and international care guidelines.

Closely related to the question of whether a therapy works (outcome research), various studies on psychotherapy process research at the IPU investigate how a therapy works (process-outcome research). These studies on the impact factors and mechanisms of psychotherapy provide insights into the processes of change in therapy sessions and the course of therapy. Audio or video recordings are used to carry out in-depth analyses and evaluations that serve to ensure quality and further develop therapeutic methods. Questions on the side effects of psychotherapy and qualitative evaluations of patient and therapist perspectives on clinical research open up further perspectives.

In order to adequately clarify such questions, a mixed-methods approach is becoming increasingly established at the IPU, which combines quantitative and qualitative methods in a concept-led manner in order to research therapeutic factors in their complexity. Through the increased inclusion of qualitative methods, the concept of personalized psychotherapy will also be given greater consideration in the future.
Research into mental disorders (development, course, risk and protective factors, as well as their cognitive-affective foundations), work on neuropsychoanalysis, trauma research, (early) prevention, diagnostics, and supervision and training research complement process and outcome research with methods and approaches from related research areas and stimulate interdisciplinary discourse.

The focus on psychotherapy research and its foundations is widely networked in Germany and abroad. Some of the IPU’s research projects are carried out as part of large collaborative projects in cooperation with other universities, research institutions, and clinics.

Studies from the IPU's psychotherapeutic outpatient clinic play a key role in this. Currently, more than 500 treatments take place at this research and teaching clinic every year, and each of these therapies is evaluated as part of the psychotherapy research carried out here.

Overall, research at the HSA can be broken down as follows:

• Empirical psychotherapy research (routine outcome monitoring, ROM) at the HSA: Baseline, progress, and outcome surveys are carried out for all treatments, which can serve as a basis for further studies.
• An exemplary selection of current HSA projects at the IPU include