Complex sentence: Population health, a field which focuses on the improvement of the health outcomes for a group of individuals, has been described as consisting of three components: "health outcomes, patterns of health determinants, and policies and interventions".
Split into simpler sentences: Population health, a field which focuses on the improvement of the health outcomes for a group of individuals, has been described as consisting of three components. These are "health outcomes, patterns of health determinants, and policies and interventions".