Our research is primarily focused on two questions: Firstly, we are interested in why children, adolescents and young adults maintain dysfunctional behaviour despite the often long-term consequences. Therefore, we investigate short-term mechanisms maintaining dysfunctional behaviour from a functional perspective. Content-related we are primarily concerned with the maintaining factors of maladaptive exercise behaviour in eating disorders.
And secondly, we are interested in how we can improve the psychotherapeutic care of children and adolescents using digital tools. Together with the University Outpatient Psychotherapy Centre for Children and Adolescents we are investigating therapy feedback systems and data-based tools to personalise child and adolescent psychotherapy.
In our methodology we primarily use two approaches: Firstly, we use everyday ambulatory assessment via smartphones and passive sensors, which give us an insight into the experience of children and adolescents in everyday life. Secondly, we use an experimental psychological focus that allows us to investigate mechanisms under randomised controlled conditions. Our movement laboratory is currently under construction.
Current research projects at the department are listed below:
Excessive or driven exercise is a common symptom of eating disorders, the maintaining mechanisms of which are poorly understood. While sport is recommended for almost all mental disorders, it is often taboo in the treatment of eating disorders and even forbidden during inpatient therapy. In chronic eating disorders, the behaviour can also appear highly ritualistic and lose all functionality. In this research field, we are investigating which maintaining mechanisms (e.g. momentary changes in emotion regulation, exercise satiation, social functions) reinforce this behaviour in the short term. In a further project, we will investigate whether short-term functions of these and other maladaptive behaviours change over the course of a mental illness and when the behaviour becomes a dysfunctional habit. For this purpose, we primarily use EMA studies, but also more and more experimental methods.
Kolar, D. R., Haynos, A., Wang, S., Lask, T., Murray, S. B., Voderholzer, U., & Gorrell, S. (in press). Identification of affective and social reinforcement functions of driven exercise: Evidence from three samples. Clinical Psychological Science. Preprint: https://osf.io/preprints/psyarxiv/ad3mq/
Huong, C., Bernstein, E. E., Curtiss, J. E., Kolar, D. R., & Brown, D. M. (2025). Network approaches for physical activity and mental health research. Sport, Exercise, and Performance Psychology, 14(1), 120–138.?https://doi.org/10.1037/spy0000371
Kolar, D. R., Ralph-Nearman, C., Swanson, T., & Levinson, C. A. 2024. Exercise moderates longitudinal group psychopathology networks in individuals with eating disorders. Comprehensive Psychiatry, 152543. https://doi.org/10.1016/j.comppsych.2024.152543
Kolar, D. R.?, Kaurin, A.?, Meule, A., Dittmer, N., Schlegl., S. & Voderholzer, U. 2022. Interpersonal, Affective and Compulsive Features of Driven Exercise in Anorexia Nervosa.Journal of Affective Disorders. 307:53–61. https://doi.org/10.1016/j.jad.2022.03.044
Kolar, D. R., Gorrell, S. 2021. A call to experimentally study acute affect-regulation mechanisms specific to driven exercise in eating disorders. International Journal of Eating Disorders. 54(3):280–286. https://doi.org/10.1002/eat.23427
Kolar, D. R., Neumayr, C., Roth, M.*, Voderholzer, U., Perthes, K.* & Schlegl, S. 2020. Testing an emotion regulation model of physical activity in adolescents with anorexia nervosa: A pilot ecological momentary assessment study. European Eating Disorders Review. 28(2):170–183. https://doi.org/10.1002/erv.2706?
At what point do we consider a sports session satisfactory and "good"? And do adolescents with eating disorders differ from healthy adolescents in this assessment? This question is addressed by the concept of Exercise Satiation. Exercise Satiation refers to the state or point in time when we are subjectively satisfied enough with our physical activity during a sports session that we voluntarily end it. This may be related to previously set goals or physical changes during exercise. In our movement laboratory, we are experimentally investigating this question.
Barker, J., Kolar, D. R., Spotts-deLazzer, A., & Keel, P. K. 2022. Exercise Satiation:
A Novel Theoretical Conceptualization for Problematic Exercise Observed in Eating
Disorders. International Journal of Eating Disorders. 55(2):176–179. https://doi.org/10.1002/eat.23635
Each patient is unique in his/her experience, however, we still know very little about how to ideally adapt psychotherapy to each child or adolescent, which is why we still do not provide all children and adolescents with the optimal intervention. In practice, individualisation often happens through clinical decisions made by practitioners. We are investigating the extent to which data-driven algorithms, which make data-driven recommendations based on a multitude of measurements in the everyday life of the patient or over the course of psychotherapy, can optimally adapt the treatment for the patient. For this, we will use EMA, passive sensing through wearables and digital therapy feedback systems in the University Outpatient Psychotherapy Clinic for Children and Adolescents.
Kaurin, A. & Kolar, D. R. 2022. Ambulantes Assessment in der Klinischen Kinderund
Jugendpsychologie. Psychotherapie. https://doi.org/10.1007/s00278-022-00605-x
Kolar, D. R., Huss, M., Jenetzky, E. & Hammerle, F. 2017. A smartphone-enhanced
low-threshold intervention for adolescents with anorexia nervosa (SELTIAN): Study
protocol of a randomized controlled trial. BMJopen 7:e018049. doi.org/10.
1136/bmjopen-2017-018049
With the help of perceived causal networks (PECAN networks) patients can establish connections between their most priority problems. The focus here is on how, from the patient's perspective, existing problems are caused and maintained. Our aim is to use PECAN networks to adapt psychotherapeutic diagnosis and treatmend more precisely to the needs of individual patients and improve them accordingly. There is already some positive scientific evidence for the use of PECAN networks with adults. This is still lacking for use with children and adolescents.
The aim of this study is therefore to investigate the practicability and usefulness of PECAN networks in the psychotherapeutic care of children and adolescents.
Selected publications in peer-reviewed journals of the Clinical Child and Adolescent Psychology and Psychotherapy.
? shared authorship
2025
Tsarpalis-Fragkoulidis, A., Kolar, D. R., Schneckenreiter, C., & Zemp, M. Emotion Regulation and Positivity Impairment in the Everyday Life of Socially Anxious Adolescents – An Ecological Momentary Assessment (EMA) Study. Kindheit und Entwicklung. Preregistration: https://osf.io/srvj3
Asbrand, J., Calvano, C., Crombach, A., Hanisch, C., Hartmann-Firnkorn, A., Hechler, T., Heinreichs, N., In-Albon, T., Jungmann, S., Kaurin, A., Kolar, D. R., et al. 2025. Das neue Psychotherapeutengesetz: Rückblick auf drei Jahre und Beispiele universit?rer Umsetzung in der Klinischen Kinder- und Jugendpsychologie und -psychotherapie. Kindheit und Entwicklung. https://doi.org/10.1026/0942-5403/a000482?
Meule, A., Seufert, L., & Kolar, D. R. 2025. Emetophobia (fear of vomiting): A meta-analysis. Journal of anxiety disorders, 114, 103053. https://doi.org/10.1016/j.janxdis.2025.103053?Preregistration: https://osf.io/tgdez?Data & code: https://osf.io/m6h45?Preprint: https://osf.io/mb47h_v1/??
Sicorello, M., Elsaesser, M., & Kolar, D. R. 2025. A German version of the State Difficulties in Emotion Regulation Scale (S-DERS): Translation, Validation and Extended Factor Models. Borderline personality disorder and emotion dysregulation, 12(1), 25. https://doi.org/10.1186/s40479-025-00299-y?Preregistration: https://osf.io/2d84m?Data & Code: https://osf.io/ebj6u/?Preprint: https://osf.io/8mzvu??
Kolar, D. R. & Meule, A. 2025. The next ten years of emotion regulation research in anorexia nervosa: positive, interpersonal, and interventional. Clinical Psychology: Science and Practice. 32(1): 23–25. https://doi.org/10.1037/cps0000263??
Meule, A., Ertl, S., Mindrup, L. M., Forbush, K. T., Ehrenthal, J. C. & Kolar, D. R. 2025. Psychometric properties of the German version of the Eating Pathology Symptoms Inventory. Journal of Eating Disorders 13, 60. https://doi.org/10.1186/s40337-025-01253-7?Data & Code: https://osf.io/95fb3/?Preregistration: https://osf.io/e8rjv?Preprint: https://osf.io/ac3bu?
2024
Kolar, D.R., Haynos, A.F., Wang, S.B., Lask, T.*, Murray, S.B., Vorderholzer, U. & Gorrell, S. 2024. Identification of affective and social reinforcement functions of driven exercise: Evidence from three samples. Clinical Psychological Science. Preprint: https://psyarxiv.com/ad3mq/?Preregistration: https://osf.io/gjfc2?Data & Code: https://osf.io/28fpv??
Huong, C., Bernstein, E. E., Curtiss, J. E., Kolar, D. R. & Brown, D. M. 2024. Network Approaches for Physical Activity and Mental Health Research. Sport, Exercise and Performance Psychology. https://doi.org/10.1037/spy0000371?Preprint: https://doi.org/10.31219/osf.io/v9j23?Data & Code: https://github.com/christopherhuong/pa_network_paper?
Kolar, D. R., Ralph-Nearman, C., Swanson, T., & Levinson, C. A. 2024. Exercise moderates longitudinal group psychopathology networks in individuals with eating disorders. Comprehensive Psychiatry, 152543. https://doi.org/10.1016/j.comppsych.2024.152543?Data & Code: https://osf.io/btzvj/??
Lampe, E.W., Schaumberg, K., Kolar, D.R., Coniglio, K., Cooper, M. Chapa, D. & Gorrell, S. 2024. Working Out Measurement Overlap in the Assessment of Maladaptive Exercise. International Journal of Eating Disorders. 57(3):558-567. https://doi.org/10.1002/eat.24127?Data & Code: https://osf.io/zev8c?
Kolar, D.R., Monteleone, A.M., Cascino, G., Ertl, S., Meule, A., Naab, S. & Vorderholzer, U. 2024. Pathways between childhood trauma, psychological symptoms and life satisfaction: a network analysis of adolescent inpatients. Research on Child and Adolescent Psychopathology. 1–14. https://doi.org/10.1007/s10802-024-01172-2? Data & Code: https://osf.io/pyke9/??
2023
Andres, F.E., Thornborrow, T., Bowie, W.N., Coneo, A.M.C., Gdl, R., Evans, E.H., Acu?a, L.S.F., Kolar, D.R., Mebarak Chams, M.R., Castro, J.C.T. & Boothroyd, L.G. 2023. Validation of a Latin American Spanish version of the Body Steem Scale for Adolescents and Adults (BESAA-LA) in Colombian and Nicaraguan adults. Journal of Eating Disorders. 11(1): 219. https://doi.org/10.1186/s40337-023-00942-5?Data & Code: https://osf.io/q9mj2/??
Kolar, D. R.?, Meule, A.?, Schwartz, C. & Voderholzer, U. 2023. Effects of acceptance-based strategies on psychological responses to disorder-relevant stimuli in inpatients with obsessive–compulsive disorder: an experimental study. Journal of Behavior Therapy and Experimental Psychiatry. 81:101890. https://doi.org/10.1016/j.jbtep.2023.101890? Data & Code: https://osf.io/whmcy??