Search results for "Cohort effect"

Population dynamic consequences of delayed life-history effects

2002

Evidence from wildlife and human populations indicates that conditions during early development can have marked effects on the subsequent performance of individuals and cohorts. Likewise, the effects of maternal and, more generally, parental environments can be transferred among individuals between generations. These delayed life-history effects are found consistently and suggestions have been made that they can be one source of both variability and of delayed density dependence in population dynamics. Assessments of several different time series indicate that population variability and delayed density dependence are common and that understanding the mechanisms giving rise to them is crucia…

HCV genotypes in Sicily: is there any evidence of a shift?

2009

The distribution of HCV strains in any area is characterized by a relative prevalence of one genotype, and a number of less prevalent types. In some Western countries a change from the prevalent HCV genotype 1 to genotypes 3 and 4 has been reported in the last decade. In order to assess possible variations of the distribution of HCV genotypes in Sicily, a southern region of Italy, a hospital-based cohort, collected prospectively, of 3,209 subjects with chronic HCV infection was surveyed, comparing the distribution of HCV genotypes during two consecutive periods, from 1997 to 2002 and from 2003 to 2007, according to age and gender. The results show that genotype 1b, which has been historical…

Changes in lung-cancer mortality trends in Spain

2001

Several changes in smoking patterns over the past decades in Spain can be expected to result in a shift in lung-cancer mortality rates. We examined time trends in lung-cancer mortality from 1973-1997 using a log-linear Poisson age-period-cohort model. The standardized lung-cancer mortality rate for men almost doubled, from 31.4 per 100,000 in 1973 to 58.6 in 1997, with an average annual increase of 2.7%. Mortality increased for male generations born until 1952 as a consequence of the increasing cigarette smoking in successive birth cohorts. However, the slight downward trend observed for the 2 youngest generations suggests a more favorable outcome of the lung-cancer epidemic among Spanish m…

Life-cycle effects in small business finance

2017

This paper studies the life-cycle profiles of small firms’ cost and use of credit using a panel of Finnish firms. The choice of method matters for the conclusions drawn about the relationship between firm age and financing costs; the cross-sectional age profiles of financing costs are hump-shaped and consistent with hold-up theories, whereas methods that control for cohort fixed effects demonstrate that the financing costs decrease monotonically as the firms mature. The life-cycle profiles of the use of credit also indicate that firms are more dependent on financial intermediaries in the early periods of their lives. Furthermore, the cohorts born during recessions pay higher financing costs…

2018

Population aging increases the need for knowledge on positive aspects of aging, and contributions of older people to their own wellbeing and that of others. We defined active aging as an individual’s striving for elements of wellbeing with activities as per their goals, abilities and opportunities. This study examines associations of health, health behaviors, health literacy and functional abilities, environmental and social support with active aging and wellbeing. We will develop and validate assessment methods for physical activity and physical resilience suitable for research on older people, and examine their associations with active aging and wellbeing. We will examine cohort effects o…

Procrastination, Distress and Life Satisfaction across the Age Range – A German Representative Community Study

2016

Addressing the lack of population-based data the purpose of this representative study was to assess procrastination and its associations with distress and life satisfaction across the life span. A representative German community sample (1,350 women; 1,177 men) between the ages of 14 and 95 years was examined by the short form of the General Procrastination Scale (GPS-K; 1) and standardized scales of perceived stress, depression, anxiety, fatigue and life satisfaction. As hypothesized, procrastination was highest in the youngest cohort (14-29 years). Only in the youngest and most procrastinating cohort (aged 14 to 29 years), men procrastinated more than women. As we had further hypothesized,…

Temporal trends in the incidence rate of childhood cancer in Germany 1987-2004.

2007

The German Childhood Cancer Registry regularly presents graphs of childhood cancer incidence rates by period, but no systematic analysis. The Automated Childhood Cancer Information System-project found an increasing trend in Europe. Against this background we present the first detailed trend analysis of childhood (aged under 15) malignancies in Germany. We examined incidence rates separately in western Germany 1987-2004 and eastern Germany 1991-2004. We analyzed all malignancies, all main diagnostic groups and relevant subsets using an age-period-cohort model. Additionally we fitted fractional polynomials to assess the linearity of the drift. All malignancies combined (excluding Central Ner…

Surrounding Greenness and Pregnancy Outcomes in Four Spanish Birth Cohorts

2012

Background: Green spaces have been associated with improved physical and mental health; however, the available evidence on the impact of green spaces on pregnancy is scarce. Objectives: We investigated the association between surrounding greenness and birth weight, head circumference, and gestational age at delivery. Methods: This study was based on 2, 393 singleton live births from four Spanish birth cohorts (Asturias, Gipuzkoa, Sabadell, and Valencia) located in two regions of the Iberian Peninsula with distinct climates and vegetation patterns (2003–2008). We defined surrounding greenness as average of satellite-based Normalized Difference Vegetation Index (NDVI) (Landsat 4–5 TM data at …

Age–Period–Cohort Analysis of Stroke Incidence in Dijon From 1985 to 2005

2010

Background and Purpose— Variations in stroke incidence could be explained by changes in vascular and environmental factors that affect the risk of stroke and changes in risk factors that are present in early life. The aim of this study was to identify and measure the effects of 3 interrelated factors, age, calendar period of stroke onset, and birth year cohort, on the incidence rates of stroke from 1985 through 2005. Methods— Age–period–cohort models were used to analyze stroke incidence in Dijon from 1985 to 2005 from a population-based registry that collects data on all stroke patients whatever the type of management, in the public hospital, private hospitals, or at home, in the populati…

Body size at birth and age-related macular degeneration in old age

2019

Purpose To study associations between body size at birth and age-related macular degeneration (AMD) in old age. Methods The study sample consists of 1497 community-dwelling individuals (56.1% women) aged 67-89 years with birth data and retinal data collected twice in old age 5 years apart. Birth data (weight, length, birth order) were extracted from original birth records. Digital retinal photographs were graded to determine AMD status. Data on covariates were collected at the baseline physical examination in old age. Multivariable regression analyses were used to study the association between birth data and AMD adjusting for known confounding factors, including birth year cohort effects. R…