Week 2 Quantifying disease - summary measures of population health

Question 1

What is life expectancy?

Answer 1

Expected age at death in years

Question 2

What is disability-free life expectancy (DFLE)

Answer 2

Measure of average number of years a person is expected to live without disability

Question 3

What is quality adjusted life years (QALYs)

Answer 3

A measure that combines both the quantity and quality of life into a single metric

Question 4

What is health adjusted life expectancy (HALE)?

Answer 4

A measure that combines life expectancy with health status of a population.

Estimates number of years a person is expected to life in good health based on prevalence of diseases and disability in the population

Question 5

What is disability adjusted life years (DALYs)

Answer 5

Combined years of life lost (YLL) due to death + years of healthy life lost due to disability (YLD) weighted by severity of the disability (0 = perfect health 1 = death)
DALY = YLL + YLD

Question 6

How do you calculate years of life lost (YLL)

Answer 6

Number of deaths at each age x standard life expectancy for each age

Question 7

How do you calculate years lived with disability (YLD)

Answer 7

Number of incident cases in a specific period x average duration of the disease x weight factor

Question 8

How do you calculate global burden of disease (GBD)

Answer 8

Using DALY’s (YLL + YLD for a specific disease)

Question 9

What does 1 DALY mean?

Answer 9

1 lost year of healthy life