HALYS and QALYS and DALYS, Oh My: similarities and differences in summary measures of population Health.

  title={HALYS and QALYS and DALYS, Oh My: similarities and differences in summary measures of population Health.},
  author={Marthe R. Gold and David Stevenson and Dennis G. Fryback},
  journal={Annual review of public health},
Health-adjusted life years (HALYs) are population health measures permitting morbidity and mortality to be simultaneously described within a single number. They are useful for overall estimates of burden of disease, comparisons of the relative impact of specific illnesses and conditions on communities, and in economic analyses. Quality-adjusted life years (QALYs) and disability-adjusted life years (DALYs) are types of HALYs whose original purposes were at variance. Their growing importance and… 

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