Chapter 2 Recap

Table 2.1: Health Metrics Overview from Chap 2

Metric	Purpose	Focus	Usage	Calculation
QALY (Quality-Adjusted Life Year)	Measures health benefits of interventions by combining quantity and quality of life gained	Health gains from interventions	Used in cost-effectiveness studies, healthcare resource allocation, and insurance	Calculated by adjusting life years gained for quality of life (e.g., 1 year at half quality = 0.5 QALY)
DALY (Disability-Adjusted Life Year)	Measures burden of disease by capturing premature death and disability impact	Health loss due to disease and disability	Used in public health to understand and compare disease burden globally	Calculated by summing years of life lost (YLL) and years lived with disability (YLD)
HALY (Health-Adjusted Life Year)	General measure combining health quantity and quality; similar to QALY but less common	Health gains or losses from interventions or disease impact	Used similarly to QALY, though less frequently in decision-making	Calculated by adjusting life years for health quality; similar to QALY
HALE (Healthy Life Expectancy)	Estimates life expectancy in ‘healthy’ years, adjusting for disability and illness	Overall healthy life expectancy at a population level	Primarily used in population health and public health reports for health expectancy	Calculated by adjusting total life expectancy based on age-specific disability prevalence
HLY (Health Life Years)	Measures the additional healthy years expected, often from a specific age like 65	Healthy life expectancy focused on ageing populations	Used in geriatric health assessments and interventions for ageing populations	Typically calculated by estimating additional years of good health beyond a baseline age
WAHE (Well-being Adjusted Health Expectancy)	Incorporates both physical and subjective well-being for life expectancy in ‘full health’	Overall well-being and mental health as well as physical health	Applicable for holistic health assessments, incorporating quality of life and mental wellness	Calculated by weighting health states to reflect impact on well-being and quality of life