Prof. Hak is chair of the Groningen Research Institute of Pharmacy unit Pharmacotherapy, -Epidemiology and -Economics. His multidisciplinary team have supervised >30 PhD theses on the applicability and validity of epidemiological causal design methods to assess (side-)effects of drugs and vaccines using Real-World Big Health Care and Biobank Data. Scientific methods consider a variety of designs such as case-control, cohort, case-only, sibling designs, instrumental variable analysis, propensity score analysis often in combination with RCTs, meta-analyses and Individual Patient Data designs. As leader of the PharmLines Initiative,  a public-private collaboration between Lifelines BV-UMCG-RUG, he initiates and co-supervises research in the area of Precision Medicine with linked pharmacy, biobank, genetic, clinical and other health care data of >100,000 persons from the Northern region. In addition, his team supports the societal impact by studying the optimal methods to implement innovations in the area of sustainable drug research such as drug repurposing and methodologies to support optimal drug use.