YLL Calculation

• Measures years lost due to premature death.
• Introduced by William Haenszel in the late 1940s.
• Formalized by Mary Dempsey in 1947 to assess tuberculosis burden.
• Formula:
  • $YLL = N \cdot le$
  • $N$ = Number of premature deaths
  • $le$ = Standard life expectancy at current age