Quality of life in general refers to the well-being of a person or population, and health-related quality of life (HRQoL) specifically is a multi-disciplinary concept encompassing the physical, mental, and social well-being of a person. HRQoL is subjective because it describes both the health status of a patient and the value associated with that health status. The manual of the National Institute for Health and Care Excellence (NICE) in the United Kingdom recommends that HRQoL be assessed by patients and weighted according to the preferences of the general population. The HRQoL is then incorporated into calculations of QALYs in a cost-effectiveness analysis.