The effect of a single dose of DEC 6 mgkg body weight on Ascaris and hookworm infections

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Hypothesis testing
It has been suggested that factors leading to the
low life expectancy for Danish women, are acting
on all women in a given time period.
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Birth cohort effects on mortality in Danish women
Rune Jacobsen Professor Elsebeth
Lynge Professor Niels Keiding
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Motivation
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Motivation
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MotivationIndications of cohort effect
Cohort period - age 1985 - 52 1933
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Questions

• Calendar period or birth cohort effect ?

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Methods age-period-cohort analysis
In-determinacy
Age period - cohort
Deviations from linearity
log(rateij) µ ?i ?j ?c
Common age effect model
log(ratekij) µk ?i ?jk ?ck
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Model selection
Clayton and Schifflers 1987
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Model validation - Danish women
80-84
50-54
65-69
45-49
75-79
60-64
70-74
55-59
40-44
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ResultsMortality of Danish women and men
Period 1960-1999 age 40-84, 5 years groups
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ResultsCompared to women in Sweden and Norway
Period 1960-1999 age 40-84, 5 years groups
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Causes of death - Smoking related
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Smoking prevalence of Danish women (possible
confounding ?)
1940-1949
percent smokers
1920-1929
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Summary

• The high risk of dying among Danish women is
  associated with being born between the two world
  wars

• Similar patterns is not found for Danish men nor
  women in Sweden and Norway

• Causes of death analysis and data on smoking
  prevalence indicate smoking as a major reason for
  the observed cohort effect

• The hypothesis that causal factors for the low
  life expectancy are acting on all Danish women
  must be rejected based on these findings.

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