Disability-Adjusted Life Years (DALYs) are calculated as which components?

• A. Disability-Adjusted Life Years equal years of life lost only.
• B. Disability-Adjusted Life Years combine years of life lost and years lived with disability.
• C. Disability-Adjusted Life Years equal years lived with disability only.
• D. Disability-Adjusted Life Years are the number of deaths in a population.

Answer: (B)

Disability-Adjusted Life Years measure total disease burden by adding two pieces: years of life lost due to premature death and years lived with disability. Years of life lost captures how many years people die earlier than a standard life expectancy. Years lived with disability accounts for the time someone lives with illness or disability, weighted by how severe that disability is. The disability weight ranges from 0 (perfect health) to 1 (death), and you multiply this weight by the duration of the condition to get years lived with disability. By summing these two components, you get a single figure that reflects both fatal and non-fatal health outcomes in a population. So DALYs are not just deaths or just disability alone; they integrate both to quantify overall burden.