Friday, February 20, 2015

Mortality Trajectories at Extreme Old Ages

Dear Colleagues,

We are pleased to alert you that our new peer-reviewed study on Mortality Trajectories at Extreme Old Ages is now publicly available at PubMed Central® (PMC) - a free full-text archive of biomedical and life sciences journal literature at the U.S. National Institutes of Health's National Library of Medicine (NIH/NLM):

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4318539/

Comments and suggestions are most welcome!

Kind regards,

-- Leonid and Natalia

-------------------------------------------------
-- Leonid Gavrilov, Ph.D., GSA Fellow
-- Natalia Gavrilova, Ph.D., GSA Fellow
Center on Aging, NORC at the University of Chicago
Website: http://longevity-science.org/

==========================================

Mortality Trajectories at Extreme Old Ages:
A Comparative Study of Different Data Sources on U.S. Old-Age Mortality

Gavrilova N.S., Gavrilov L.A.
In: 2014 Living to 100 Monograph
[available in PMC 2015 Feb 5 ].
The Society of Actuaries, 2014, 23 pages, PMID: 25664347

Abstract:

The growing number of individuals living beyond age 80 underscores the need for accurate measurement of mortality at advanced ages. Our earlier published study challenged the common view that the exponential growth of mortality with age (Gompertz law) is followed by a period of deceleration, with slower rates of mortality increase (Gavrilov and Gavrilova 2011). This refutation of mortality deceleration was made using records from the U.S. Social Security Administration’s Death Master File (DMF).

Taking into account the significance of this finding for actuarial theory and practice, we tested these earlier observations using additional independent datasets and alternative statistical approaches. In particular, the following data sources for U.S. mortality at advanced ages were analyzed: (1) data from the Human Mortality Database (HMD) on age-specific death rates for 1890–99 U.S. birth cohorts, (2) recent extinct birth cohorts of U.S. men and women based on DMF data, and (3) mortality data for railroad retirees.

In the case of HMD data, the analyses were conducted for 1890–99 birth cohorts in the age range 80–106. Mortality was fitted by the Gompertz and logistic (Kannisto) models using weighted nonlinear regression and Akaike information criterion as the goodness-of-fit measure. All analyses were conducted separately for men and women. It was found that for all studied HMD birth cohorts, the Gompertz model demonstrated better fit of mortality data than the Kannisto model in the studied age interval. Similar results were obtained for U.S. men and women born in 1890–99 and railroad retirees born in 1895–99 using the full DMF file (obtained from the National Technical Information Service, or NTIS). It was also found that mortality estimates obtained from the DMF records are close to estimates obtained using the HMD cohort data.

An alternative approach for studying mortality patterns at advanced ages is based on calculating the age-specific rate of mortality change (life table aging rate, or LAR) after age 80. This approach was applied to age-specific death rates for Canada, France, Sweden and the United States available in HMD. It was found that for all 24 studied single-year birth cohorts, LAR does not change significantly with age in the age interval 80–100, suggesting no mortality deceleration in this interval. Simulation study of LAR demonstrated that the apparent decline of LAR after age 80 found in earlier studies may be related to biased estimates of mortality rates measured in a wide five-year age interval.

Taking into account that there exists several empirical estimates of hazard rate (Nelson-Aalen, actuarial and Sacher), a simulation study was conducted to find out which one is the most accurate and unbiased estimate of hazard rate at advanced ages. Computer simulations demonstrated that some estimates of mortality (Nelson-Aalen and actuarial) as well as kernel smoothing of hazard rates may produce spurious mortality deceleration at extreme ages, while the Sacher estimate turns out to be the most accurate estimate of hazard rate. Possible reasons for finding apparent mortality deceleration in earlier studies are also discussed.

This study was supported in part by National Institutes of Health grant R01 AG028620

-----------------------------------------------------

5 Comments:

Blogger ninest123 Ninest said...

ninest123 12.30
prada handbags, tory burch outlet, louis vuitton, polo ralph lauren outlet, louboutin outlet, ray ban sunglasses, louis vuitton outlet, louis vuitton, louis vuitton outlet, longchamp outlet, replica watches, christian louboutin outlet, louboutin shoes, jordan shoes, longchamp outlet, polo ralph lauren outlet, replica watches, michael kors outlet, ray ban sunglasses, louis vuitton, michael kors outlet, nike free, michael kors outlet, burberry, longchamp, cheap oakley sunglasses, gucci outlet, ugg boots, michael kors outlet, michael kors, ugg boots, oakley sunglasses, ray ban sunglasses, nike air max, ugg boots, uggs on sale, tiffany and co, michael kors outlet, oakley sunglasses, prada outlet, tiffany jewelry, burberry outlet online, oakley sunglasses, ugg boots, nike air max, nike outlet, louboutin, chanel handbags, oakley sunglasses

6:53 PM  
Blogger ninest123 Ninest said...

north face, nike roshe, vans pas cher, replica handbags, air force, timberland, lululemon, sac longchamp, ralph lauren pas cher, vanessa bruno, hollister pas cher, true religion jeans, air jordan pas cher, true religion jeans, nike huarache, hermes, true religion outlet, hollister, michael kors, nike air max, michael kors, nike blazer, michael kors, ralph lauren uk, longchamp pas cher, hogan, lacoste pas cher, true religion jeans, nike trainers, mulberry, michael kors, nike free, oakley pas cher, louboutin pas cher, longchamp, north face, nike roshe run, coach outlet, new balance pas cher, ray ban uk, ray ban pas cher, abercrombie and fitch, tn pas cher, nike air max, sac guess, nike air max, air max, burberry, converse pas cher, nike free run uk, coach purses

6:54 PM  
Blogger ninest123 Ninest said...

louboutin, reebok shoes, s5 cases, valentino shoes, iphone 5s cases, herve leger, gucci, beats by dre, ralph lauren, instyler, vans shoes, new balance, wedding dresses, north face outlet, nike roshe, hollister, nike air max, mac cosmetics, ray ban, abercrombie and fitch, ferragamo shoes, nike air max, p90x workout, jimmy choo shoes, insanity workout, ghd, lululemon, mont blanc, converse, asics running shoes, nfl jerseys, iphone 6s cases, birkin bag, bottega veneta, iphone 6 plus cases, baseball bats, vans, soccer shoes, north face outlet, iphone 6 cases, celine handbags, hollister, soccer jerseys, oakley, iphone cases, giuseppe zanotti, chi flat iron, timberland boots, mcm handbags, ipad cases, babyliss, iphone 6s plus cases

6:56 PM  
Blogger ninest123 Ninest said...

links of london, moncler, ugg pas cher, sac louis vuitton pas cher, moncler, louis vuitton, bottes ugg, canada goose, moncler, pandora charms, marc jacobs, canada goose, supra shoes, karen millen, canada goose outlet, barbour, doke gabbana outlet, montre pas cher, canada goose, pandora jewelry, hollister, pandora charms, ugg,uggs,uggs canada, canada goose uk, louis vuitton, moncler, coach outlet, pandora jewelry, doudoune canada goose, juicy couture outlet, thomas sabo, ugg boots uk, barbour jackets, louis vuitton, moncler, toms shoes, ugg,ugg australia,ugg italia, replica watches, swarovski, moncler outlet, canada goose, swarovski crystal, lancel, moncler, wedding dresses, juicy couture outlet, louis vuitton, canada goose outlet, moncler, converse outlet
ninest123 12.30

6:59 PM  
Blogger Zheng junxai5 said...

zhengjx20160524
louis vuitton bags
louis vuitton purses
hollister clothing
louis vuitton handbags
ray ban wayfarer
polo ralph lauren outlet
hollister clothing store
lebron 12
supra footwear
michael kors outlet clearance
coach outlet store
nfl jerseys
cheap ray ban sunglasses
nike sb janoski
adidas wings
christian louboutin sale
coach factory outlet online
nike air max uk
tory burch boots
concords 11
adidas superstar trainers
adidas outlet store
true religion jeans
louis vuitton outlet
coach factory outlet
nike store
michael kors bags
michael kors outlet clearance
kate spade outlet
louis vuitton outlet
oakley vault
louis vuitton outlet online
michael kors bags
louis vuitton purses
michael kors outlet online sale
michael kors outlet
true religion outlet
celine bags
michael kors outlet online
coach outlet

2:16 AM  

Post a Comment

Links to this post:

Create a Link

<< Home