Calculating expected years of life lost for assessing local ethnic disparities in causes of premature death

BMC Public Health

Table 1 Summary of notation and definitions

Notation	Definition
Introduced in Equation 1
x	Age
n	Age interval length
e _x	Life expectancy at age x
$e_{x}^{s}$	Standard life expectancy at age x
$_{n} e_{x}^{s}$	Standard life expectancy for age interval x to x + n
_n a _x	Average age of death for age interval x to x + n
Introduced in Equations 2 to 5
_n Y _x	Expected years of life lost for age interval x to x + n
_n D _x	Number of deaths in age interval x to x + n
r	Discount rate (usually set to 0.03)
K	Age-weighting modulation constant (K = 0, no weighting; K = 1, weighting)
β	Age-weighting constant (set to β = 0.04)
C	Adjustment constant for age-weights (set to 0.1658)
Y LL	Expected years of life lost (Y LL = ∑_n Y _x)
Equation 6
ASY R	Age-standardized Y LL rate (∑ $_{n} y_{x}^{s}$ )
$_{n} y_{x}^{s}$	Weighted expected years of life rate for age interval x to x + n
_n y _x	Expected years of life lost rate for age interval x to x + n
_n N _x	Population (person-year) estimate for age interval x to x + n
_n w _x	Year 2000 United States standard population as weights (∑_n w _x= 1)
_n W _x	Year 2000 United States standard population (∑_n W _x= 1,000,000)

ISSN: 1471-2458