Within the life-cycle assessment of health technologies, real-world data (RWD) have until now been of secondary importance to clinical trial data. The availability of massive, better quality RWD, particularly with the emergence of connected devices, the improvement of methods for characterizing populations, make it possible to have a better insight into the effects of treatment, sometimes on a national scale the importance of RWD is likely to progress in the eyes of health technology assessors, going from being traditionally complementary to possibly replacing clinical trial data.