Welcome to my website! I am an applied statistician and (pharmaco)epidemiologist with a special interest in advanced statistical methods for counterfactual causal inference and an emerging interest in machine learning.

Recently, I decided to switch tracks and took up a position as Clinical Data Scientist at the Comprehensive Cancer Institute Netherlands (IKNL). In this new position, I will once again have more time to personally perform research that matters, while also being much closer to real world implementation of that research.

I continue my commitments to academic science as well, though! I retain an affiliation with the Groningen Research Institute of Pharmacy, University of Groningen, where I supervise PhD students Irene Mommers and Stefan Verweij on the topic of Precision Drug Therapy & Real World Evidence.  I also retain an affiliation with the Max Planck Institute for Demographic Research (MPIDR), where previously I was the Deputy Head of the Population Health laboratory. At MPIDR, I supervise the work of PhD student Maria Gueltzow, who studies mental health using advanced statistical methods.


See the rest of this site for my CV, Publications, an archive of my blog posts, and my contact info.

Since I get asked questions about it: my surname comes from Frisian. If you don’t know how to pronounce it, following English orthography just say ‘Bell-sma’ or ‘Beel-sma’ (either way is fine).