Disentangling rectangularization and life span extension with the moving rectangle method

TY - JOUR

T1 - Disentangling rectangularization and life span extension with the moving rectangle method

AU - Schalkwijk, Frank H

AU - Koopman, Jacob J E

AU - Ghariq, Eidrees

AU - de Beer, Joop A A

AU - van Bodegom, David

AU - Westendorp, Rudi G J

N1 - Copyright © 2016 Elsevier Inc. All rights reserved.

PY - 2016/3/1

Y1 - 2016/3/1

N2 - PURPOSE: The moving rectangle method is used to disentangle the contributions of rectangularization and life span extension to the increase in life expectancy. It requires the choice of an endpoint of the survival curve that approaches the maximum age at death. We examined the effect of choosing different end points on the outcomes of this method.METHODS: For five developed countries, survival curves from age 50 years were constructed per calendar year from 1922 onward. Survival values of 0.1, 0.01, and 0.001 were chosen as end points of the survival curve, and the contributions of rectangularization and life span extension to the increase in life expectancy were calculated using the moving rectangle method.RESULTS: The choice of different survival values as end points profoundly influenced the estimated contributions of rectangularization and life span extension to the increase in life expectancy. When choosing 0.001, rectangularization contributed most years, whereas when choosing 0.1, life span extension contributed most years.CONCLUSIONS: When the moving rectangle method is used to estimate the contributions of rectangularization and life span extension to the increase in life expectancy, its outcomes depend on the choice of the endpoint of the survival curve.

AB - PURPOSE: The moving rectangle method is used to disentangle the contributions of rectangularization and life span extension to the increase in life expectancy. It requires the choice of an endpoint of the survival curve that approaches the maximum age at death. We examined the effect of choosing different end points on the outcomes of this method.METHODS: For five developed countries, survival curves from age 50 years were constructed per calendar year from 1922 onward. Survival values of 0.1, 0.01, and 0.001 were chosen as end points of the survival curve, and the contributions of rectangularization and life span extension to the increase in life expectancy were calculated using the moving rectangle method.RESULTS: The choice of different survival values as end points profoundly influenced the estimated contributions of rectangularization and life span extension to the increase in life expectancy. When choosing 0.001, rectangularization contributed most years, whereas when choosing 0.1, life span extension contributed most years.CONCLUSIONS: When the moving rectangle method is used to estimate the contributions of rectangularization and life span extension to the increase in life expectancy, its outcomes depend on the choice of the endpoint of the survival curve.

U2 - 10.1016/j.annepidem.2015.12.010

DO - 10.1016/j.annepidem.2015.12.010

M3 - Letter

C2 - 26847052

SN - 1047-2797

VL - 26

SP - 218-221.e2

JO - Annals of Epidemiology

JF - Annals of Epidemiology

IS - 3

ER -