Assortative mating for IQ: a multivariate approach.
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Adult↗
Biomedical subjects
J L Boldsen
Publications and source records attributed to J L Boldsen.
A continuous decline in menarcheal age in Denmark.
We report a renewed decline in mean menarcheal age in a large Danish sample after a period with a halt in the trend towards earlier age at menarche in many North European countries. In our study based on retrospective data from six different samples constituting 42784 women, we find a continuously declining mean menarcheal age in Denmark among women born in the years 1964-1973. In a sample of textile workers born in the years 1939-1968 (n = 12605) we find a 1 year higher mean menarcheal age. This indicates that menarcheal age is still delayed in certain groups in Denmark. This leaves the possibility that the menarcheal age could fall even further in the future.
Adult↗
The distribution of stature among Danish conscripts in 1852-56.
Stature measurements on large samples of unselected 22-year-old Danish males from the period 1852-56 are analysed. Data are given for 18 rural counties and the City of Copenhagen. The distribution of stature deviates significantly and systematically from Normality in all counties. A mixture of two Normal distributions with equal variances describes the empirical distribution of stature in the 18 rural counties and explains important aspects of the distribution of stature in the City of Copenhagen. This mixed structure of the population is accomplished by a factor reducing the mean stature of a fraction of the population by nearly 20 cm. The factor generating this mixed population is probably genetic and inbreeding may play a major part in raising the frequency of affected persons to the observed values, 0.2-2%. The mean stature of the majority of the population and the mixing proportion show significant geographical variation. The frequency of the small subpopulation is generally highest in the least-developed main province, Jutland, and lower on the islands, particularly in and around the City of Copenhagen. On the Zealand group of islands the mean stature of the majority of the population is highest in the most developed area, whereas the reverse occurs in Jutland.
Body Height↗
Regional and social analysis of height variation in a contemporary British sample.
The height distributions of 11-year-old boys and girls and their parents (N = 33 000) comprising the National Child Development Study are reported. The variance in height was found to differ significantly between social classes for all three family positions (father, mother and child). Analysis of variance and cluster analysis revealed that stature distributions in all three family positions is more socially rather than regionally differentiated.
Body Height↗
Recalled age of menarche in Britain.
The purpose of this study was to determine recalled age at menarche from the National Child Development Survey of all children born in Britain in one week of 1958. All subjects were questioned at the same age (16 years); mean age at menarche was estimated as 13.3 +/- 0.02 years. The data deviate significantly from normality. Marked regional variation occurred but very little social class differentiation was apparent.
Adolescent↗
Assortative mating, differential fertility and abnormal pregnancy outcome.
This study examines the relationship between spousal likeness in stature and two measures of reproductive success: the number of live-born children and the frequency of abnormal pregnancies, in a large British national sample. The analyses showed that as the husband-wife height difference increases so does the probability of having an abnormal pregnancy outcome. Increasing spousal similarity for height associates with increasing numbers of live-born children even after correcting for parental age, social and regional differences.
Adult↗
Body proportions in a medieval village population: effects of early childhood episodes of ill health.
The purpose of this paper is to widen the observational basis for analysing growth patterns. To reach this aim measurements taken on skeletons from a small Danish village, Tirup, are analysed in relation to evidence for ill health in early childhood (age 1-6 years, inclusive). Enamel hypoplasia is taken as the indicator of health problems in this age range. It is found that episodes of ill health in childhood played no part in the formation of adult size. In order to analyse size independent aspects of adult morphology shape related variables like residual height and principal component scores were analysed. It is found that the episodes of ill health leading to hypoplasia did indeed change the score on some size independent linear combinations of the raw measurements. It is concluded that the kind of stress in childhood leading to enamel hypoplasia probably modified the relationship between long bone lengths and stature. It appears that the association between vertebral body breadth measurements and living height is--at least in part--brought about by episodes of ill health in early childhood.
Anthropometry↗