Lex is a behavioral researcher who wrote his PhD thesis on the topic of user-centered design for personalisation.

Next, he worked as a Post-Doctoral researcher at the National Institute for Public Health and the Environment where he focused on the design and evaluation of mobile health technology and health information seeking behavior. At Roessingh Research and Development, Lex works as senior researcher and holds a research line on requirements engineering for telemedicine services. His expertise include human-centered design, requirements engineering, information design, personalization and designing for privacy and trust. Lex is associate editor for BMC Medical Informatics and Decision Making.