Jorien Treur’s research focusses on mechanisms that underlie comorbidity between different types of (mental) health disorders. She is particularly interested in causal questions. For instance, does (e-)smoking causally increase the risk of developing a depressive disorder? Or, why are people with a mental health disorder at higher risk of cardiovascular disease? Jorien obtained a MSc degree in Health Sciences in 2011 and a PhD in Behavioral Genetics in 2016 (VU University). As a post-doctoral researcher, she worked at the University of Bristol where she specialized in advanced epidemiological and genetic methods for causal inference. In 2018, she joined the Psychiatry department of Amsterdam UMC, where she now leads the Comorbidity and Causality research group. Her work has been funded by, among others, a NWO Veni grant, Young Investigator Grant (BBRF), Dekker grant (Hartstichting), and ERC-Starting Grant. Together with her team, she conducts research on various topics, important focal points being the association of mental health disorders (schizophrenia, bipolar disorder, depressive disorder, anxiety disorder, PTSD) with substance use ((e-)smoking, cannabis, alcohol) and with cardiovascular disease. She combines advanced computational approaches, including Mendelian randomization analyses, polygenic score analyses, (twin-)family designs, and (genomic) structural equation modelling, and apply these to large-scale cohort/biobank studies, taking (gender/ancestral) diversity into account. In order to obtain reliable causal evidence, Jorien makes use of ‘triangulation’; the practice of prospectively choosing, conducting and integrating two or more methods. Finally, she works with various stakeholders (experts by experience, policy officers, health professionals) to facilitate implementation of her findings to practice.