After two research fellowships in John Cryan's lab at University College Cork (2007-2009) and in Isabelle Decosterd's group at the Lausanne University Hospital (2009-2013), he took an entrepreneurial leap in 2013. Driven by a passion for scientific rigour, he founded a biostatistics consultancy to empower the next generation of life scientists with robust research methodologies. His mission? To improve researchers' literacy in data analysis and experimental design, by teaching statistics without mathematics or programming. At the Precision Medicine Unit run by Jacques Fellay (2017-2025), Gosselin has been perpetuating this commitment by teaching biostatistics (which attracted more than 600 PhD students since 2014), predictive medicine, and artificial intelligence in various Swiss doctoral schools and at the School of medicine of the University of Lausanne. 

Romain-Daniel Gosselin's commitment to scientific excellence extends beyond the classroom – he regularly publishes guidelines and methodology articles, he serves as a section editor for Laboratory Animals, contributes to the Swiss Reproducibility Network, takes part of the biostatistics task force of the 3RCC, and serves as a very active peer reviewer for numerous periodicals.