Modelling cohort seasonal mortality e ects in a compositional framework

In the late 20th century, the average age at death for Danes and Austrians aged 50 or above and born in the Spring was approximately 6 months older than those born in the Autumn (Doblhammer and Vaupel, 2001). The pattern was reversed for native-born Australians but, using British migrants to Australia as a natural experiment, these authors showed that the latter retained the northern hemisphere pattern indicating that it must have been an `early life' e ect. This indicates that the human body can experience damage or selection in early life that can be expressed as a mortality risk 50 or more years later. The problem is that month of birth is simply an indicator. We do not know if these e ects occured during pregnancy or after birth. Those born in the Spring were in utero during the winter, which may have been bad for the mother's health and therefore their own development, but they also experienced the Spring peak in infant respiratory infections. Bengtsson and Lindstr om (2003) used historic data for southern Sweden to show that mortality risk after the age of 50 was higher if the person was born in a year with above average infant mortality. This suggests that, on balance, the survivors of a bad year were not more robust (selection) but had been damaged by the experience (debility)

Modelling and forecasting healthy life expectancy. A Compositional Data Analysis approach

Will the extra years of life gained by the increase in life expectancy be lived in good or bad health? As forecasts support social, economic and medical decisions, as well as individuals' choices, there is a clear rationale for forecasting healthy life expectancy. However, only a limited number of models are available to forecast healthy life expectancy. Some are based on multistate modelling, which can be data-demanding and requires separate forecasts of transition rates for mortality within different health statuses and the incidence rate. We here suggest a less data demanding model to forecast mortality and health prevalence simultaneously. The model is based on the Sullivan method, which uses cross-sectional data, and Compositional Data Analysis. The method is applied to Swedish female mortality aged 65 and above. We show that deaths have been shifted towards older ages and not-limited, leading to an increase in both life expectancy and disability-free life expectancy

Re-introducing the Cambridge Group Family Reconstitutions

English Population History from Family Reconstitution 1580–1837 was important both for its scope and its methodology. The volume was based on data from family reconstitutions of 26 parishes carefully selected to represent 250 years of English demographic history. These data remain relevant for new research questions, such as studying the intergenerational inheritance of fertility and mortality. To expand their availability the family reconstitutions have been translated into new formats: a relational database, the Intermediate Data Structure (IDS) and an episode file for fertility analysis. This paper describes that process and examines the impact of methodological decisions on analysis of the data. Wrigley, Davies, Oeppen, and Schofield were sensitive to changes in the quality of the parish registers and cautiously applied the principles of family reconstitution developed by Louis Henry. We examine how these choices affect the measurement of fertility and biases that are introduced when important principles are ignored

Modelling Cohort Seasonal Mortality Effects in a Compositional Framework

In the late 20th century, the average age at death for Danes and Austrians aged 50 or above and born in the Spring was approximately 6 months older than those born in the Autumn (Doblhammer and Vaupel, 2001). The pattern was reversed for native-born Australians but, using British migrants to Australia as a natural experiment, these authors showed that the latter retained the northern hemisphere pattern indicating that it must have been an ‘early life’ effect. This indicates that the human body can experience damage or selection in early life that can be expressed as a mortality risk 50 or more years later. The problem is that month of birth is simply an indicator. We do not know if these effects occured during pregnancy or after birth. Those born in the Spring were in utero during the winter, which may have been bad for the mother’s health and therefore their own development, but they also experienced the Spring peak in infant respiratory infections. Bengtsson and Lindstr¨om (2003) used historic data for southern Sweden to show that mortality risk after the age of 50 was higher if the person was born in a year with above average infant mortality. This suggests that, on balance, the survivors of a bad year were not more robust (selection) but had been damaged by the experience (debility). The overall purpose of this research is to analyse Danish infant mortality by month of birth and month of age between 1925 and 1945 and to link this experience to the mortality risk of the survivors after 1953, based on individual death records of Danes which give age, sex and cause of death. The hypothesis is that individuals who lived through months of high infant mortality will have higher mortality risks at older ages and, second, that their deaths may be concentrated within the respiratory causes. There are also reasons to expect that any additional mortality risk will be higher if they were aged 6–12 months during a dangerous period rather than ages 0–6 months when they were protected by maternal immunity. The amplitude of monthly variation in mortality of newborn infants was low but increased to a peak when months in the late Spring interacted with ages 6–12 months. The first purpose of this paper is to explore a compositional approach to the perturbation that takes place in mortality during the first year of life with respect to month of age and time. Indicators of the seasonal concentration of mortality are frequently based on data aggregated into weeks or months and expressed as proportions of the annual total so the compositional approach is natural. The second, and more speculative, purpose is to link a set of evolving compositions in early life effects to the mortality outcomes of adult cohort

The contribution of urbanization to changes in life expectancy in Scotland, 1861-1910

During the nineteenth and early twentieth centuries, urban populations in Europe and North America continued to be afflicted by very high mortality as rapid urbanization and industrialization processes got underway. Here we measure the effect of population redistribution from (low-mortality) rural to (high-mortality) urban areas on changes in Scottish life expectancy at birth from 1861 to 1910. Using vital registration data for that period, we apply a new decomposition method that decomposes changes in life expectancy into the contributions of two main components: (1) changes in mortality; and (2) compositional changes in the population. We find that, besides an urban penalty (higher mortality in urban areas), an urbanization penalty (negative effect of population redistribution to urban areas on survival) existed in Scotland during the study period. In the absence of the urbanization penalty, Scottish life expectancy at birth could have attained higher values by the beginning of the twentieth century

Assessing the impact of antimicrobials on human ageing

Fundación BBVAN