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stdYPLL: Age‐standardized years of potential life lost

Source: R/stdYPLL.R
stdYPLL.Rd

Calculates the age‐standardized YPLL, a measure of the amount of life lost due to premature mortality.

Usage

stdYPLL(d, pop, Nref, ages = ages, K = 75, fac = 10000)

Arguments

d

a vector containing the number of deaths in each age group in the study population.

pop

a vector containing the population size for each age group within the study population.

Nref

a vector containing the population size for each age group within the reference population.

ages

a vector containing the lower limit of each age group.

K

the standard life expectancy age. The default is 75 years.

fac

a factor used to represent the mortality rate as "deaths per fac population". The default is 1e4.

Value

Returns a list with five components:

  • out: A matrix containing in its columns the number of deaths in each age group (\(d_i\)), the correspondent midpoint of age, the difference between the midpoint of age and K (\(a_i\)), the product \(a_i d_i\), the population size for each age group within the reference population, the age‑specific YPLL rates (YPLL per person), and the age‑specific YPLL, respectively.

  • ypll: The crude estimate of YPLL.

  • ypllrate: The YPLL rate in years per fac people.

  • stdypll: The age‐standardized YPLL.

  • stdypllrate: The age‐standardized YPLL rate in years per fac people.

Details

Age-Standardized Years of Potential Life Lost (ASYPLL) involves adjusting the YPLL rate of a specific population to a standard population structure to allow for fair comparisons across different regions or time periods. This measure is given by $$ASYPLL = \sum\limits_{i=1}^{K^*} \dfrac{a_i d_i}{p_i} N_i$$ where \(K^*\) is the number of age groups between 0 and K, \(a_i\) is the difference between K and the midpoint of age in each age group, assuming a uniform distribution of deaths in each group, \(d_i\) is the number of deaths in the \(i\)-th age group (d), \(p_i\) is the population size for each age group within the study population (pop), and \(N_i\) the population size for each age group within the reference population (Nref) (Silva Filho et al., 2024).

The age‐standardized YPLL rate is given by $$ASYPLL\ rate = \dfrac{ASYPLL}{\sum_{i=1}^{K^*} N_i} \times C$$ This measure is interpreted in years per \(C\) people, where \(C\) is specified by the argument fac.

References

Silva Filho, A.M.D., Araújo, E.M.D., Souza, I.M.D., Luiz, O.D.C., Máximo, G., Queiroz, F.D.A., Cavalcante, L., Nisida, V. (2024). Years of potential life lost due to COVID-19 according to race/color and gender in Brazil between 2020 and 2021. Ciência & Saúde Coletiva, 29, e04702023. doi: 10.1590/1413-81232024293.04702023EN

Examples

# Example 1
d    <- c(0,0,1,12,60,100,137,200,225,236,237,258,226)
pop  <- c(1787296,648467,752059,783322,808350,881275,892896,
          771218,713233,649157,581323,472760,356725)
Nref <- c(3906682,1396816,1584091,1655473,1730527,1873165,1902856,
          1639164,1534930,1433780,1294948,1054437,795497)
ages <- c(0,15,20,25,30,35,40,45,50,55,60,65,70)
stdYPLL(d,pop,Nref,ages)
#> $out
#>            d  mid    a     ad       P  asYPLLrates    Nref     asYPLL
#> 0 to 14    0  7.5 67.5    0.0 1787296 0.000000e+00 3906682     0.0000
#> 15 to 19   0 17.5 57.5    0.0  648467 0.000000e+00 1396816     0.0000
#> 20 to 24   1 22.5 52.5   52.5  752059 6.980835e-05 1584091   110.5828
#> 25 to 29  12 27.5 47.5  570.0  783322 7.276701e-04 1655473  1204.6382
#> 30 to 34  60 32.5 42.5 2550.0  808350 3.154574e-03 1730527  5459.0757
#> 35 to 39 100 37.5 37.5 3750.0  881275 4.255198e-03 1873165  7970.6888
#> 40 to 44 137 42.5 32.5 4452.5  892896 4.986583e-03 1902856  9488.7494
#> 45 to 49 200 47.5 27.5 5500.0  771218 7.131576e-03 1639164 11689.8231
#> 50 to 54 225 52.5 22.5 5062.5  713233 7.097961e-03 1534930 10894.8732
#> 55 to 59 236 57.5 17.5 4130.0  649157 6.362097e-03 1433780  9121.8479
#> 60 to 64 237 62.5 12.5 2962.5  581323 5.096134e-03 1294948  6599.2287
#> 65 to 69 258 67.5  7.5 1935.0  472760 4.092986e-03 1054437  4315.7957
#> 70 to 74 226 72.5  2.5  565.0  356725 1.583853e-03  795497  1259.9504
#> 
#> $ypll
#> [1] 31530
#> 
#> $ypllrate
#> [1] 31.22375
#> 
#> $stdypll
#> [1] 68115.25
#> 
#> $stdypllrate
#> [1] 31.24214
#> 

# Example 2
d <- c(10,50,20)
pop  <- c(50000,40000,10000)
Nref <- c(20000,20000,10000)
ages <- c(0,35,65)
stdYPLL(d,pop,Nref,ages)
#> $out
#>           d  mid    a   ad     P asYPLLrates  Nref asYPLL
#> 0 to 34  10 17.5 57.5  575 50000     0.01150 20000    230
#> 35 to 64 50 50.0 25.0 1250 40000     0.03125 20000    625
#> 65 to 74 20 70.0  5.0  100 10000     0.01000 10000    100
#> 
#> $ypll
#> [1] 1925
#> 
#> $ypllrate
#> [1] 192.5
#> 
#> $stdypll
#> [1] 955
#> 
#> $stdypllrate
#> [1] 191
#>