This doctoral thesis in economics examines the working conditions of hospital staff and their impact on the quality of care in France. This is a particularly topical theme, especially given the COVID-19 crisis. The main research question is: "In hospitals, does increased exposure to psychosocial risks result in a lower quality of care?" The thesis seeks to study the channels through which increased exposure to psycho-social risks can influence quality of care, in particular: 1) via their influence on the state of staff health and 2) the modifications in their professional careers. Thus, this thesis aims to develop three distinct research axes and to use appropriate econometric modeling to investigate certain predictions of economic theory.