Disentangling rectangularization and life span extension with the moving rectangle method

Research output: Contribution to journalLetterResearchpeer-review

Frank H Schalkwijk, Jacob J E Koopman, Eidrees Ghariq, Joop A A de Beer, David van Bodegom, Rudi G J Westendorp

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.

Original languageEnglish
JournalAnnals of Epidemiology
Volume26
Issue number3
Pages (from-to)218-221.e2
Number of pages6
ISSN1047-2797
DOIs
Publication statusPublished - Mar 2016

ID: 160192239