QALYs are used to measure what?

• A. Years of healthy life lost
• B. Incidence of disease per 1000
• C. Quality-adjusted life years gained
• D. Cost savings per patient

Answer: (C)

QALYs measure the combined effect of how long someone lives and how good that life is. One QALY equals one year in perfect health; a year lived in a health state valued at less than perfect health counts as less than one QALY (for example, 0.8 QALYs if the state is weighted 0.8). When a treatment extends life or improves quality of life, the gain is counted in QALYs gained. This makes QALYs a common metric for cost-utility analyses to compare the value of different medical interventions. The option that describes Quality-adjusted life years gained fits this concept. The other choices describe different measures: years of healthy life lost relates to burden of disease, incidence per 1000 is a measure of disease frequency, and cost savings per patient is an economic outcome rather than a health-quality measure.