Differences in height by education among 371,105 Dutch military conscripts

Secular trends and regional pattern in body height of Austrian conscripts born between 1961 and 2002

The human growth process is influenced not only by genetic factors but also by environmental factors. Therefore, regional differences in mean body heights may exist within a population or a state. In the present study, we described and evaluated the regional trends in mean body heights in the nine Austrian provinces over a period spanning more than four decades. Body height data of 1734569 male conscripts born in Austria with Austrian citizenship between 1961 and 2002 were anonymized and analyzed. From 1961 to 2002 birth cohorts, an overall increase in the mean body height of Austrian recruits was observed, although regional differences were evident. Regions with shorter body heights in the 1961-1963 birth cohorts showed a particularly pronounced increase in mean body heights. Meanwhile, the course of body height growth in the capital city, Vienna, was striking, where the highest body heights were documented for the 1961-1963 birth cohorts. In Vienna, mean body heights continued to decline until the 1984 birth cohort and increased again from the 1988 birth cohorts. In addition to economic factors, increased stress factors in an urban environment and a form of urban penalty are discussed as causes.

Re-examining the social gradient in health: A study of Dutch men, 1850-1984

Today, a social gradient in health is clearly visible. Individuals with higher socio-economic statuses tend to live longer lives, and are less likely to be disabled or chronically ill. However, there is debate over when the social gradient emerged: is it a constant across contexts, or a particular feature of certain societies? Often, social gradients are not found in historical contexts. This is perhaps because historical studies use mortality as their sole measure of health, which may not fully reflect the health statuses of the living. Using another health indicator may help to identify whether a social gradient in health was present in historical contexts. One alternative measure of health is body height, a barometer of population health. In this study, we accordingly examined socio-economic status's relationship to both adult mortality and body height. A sample of Dutch men (n=3396), born between 1850 and 1900, was used. Socio-economic status was measured with parental occupational class, and height was measured at age 20. Survival analyses (for mortality at age 20 or later) and linear regressions (for height at age 20) were performed. We found no clear gradient in occupational class's relationship to adult mortality. Regarding height, individuals from elite backgrounds were estimated to be 2.82 cm cm taller (95% CI: 1.41-4.24) than those from unskilled working backgrounds. While a gradient in height was present in earlier birth cohorts, it was not visible among men born between 1885 and 1900. These findings indicate that there was a social gradient in health in the late nineteenth and twentieth centuries, although the gradient perhaps changed based on the indicator and time period being examined. This may mean that the social gradient in health is more persistent over time than it appears when only examining the social gradient in mortality.

Height, wealth, and schooling outcomes in young women from lower- and middle-income countries

This study evaluates a large (N > 366,000) sample of young women (15-18 years) from 64 lower- and middle-income countries for associations between height, household wealth, and schooling outcomes, with a focus on secondary school attendance. A pooled sample and regional samples (Latin America, South/Southeast Asia, East Africa, and West Africa) are evaluated. A dual purpose is to evaluate both associations between height and schooling, and potential height-wealth interactions such that height associations to schooling vary over levels of wealth. Ordered probit analysis indicates positive marginal probabilities from height on secondary school attendance in all samples, with diminishing probabilities in the Latin America and South/SE Asia samples, and flat/increasing probabilities in the African samples. For South/SE Asia and taller women in Latin America, height associations are stronger at lower household wealth. For both African samples and shorter women in Latin America, height associations are stronger at higher wealth. The findings suggest that the height-schooling relationship may derive from the influence from early-life health, and may also be affected by differences in health and education environments as suggested by variations across regions and height-wealth interactions within regions.

Time trends in body height according to educational level. A descriptive study from the Tromsø Study 1979-2016

OBJECTIVES

The objective of our study was to describe time trends in body height according to attained educational level in women and men in Norway.

METHODS

We used previously collected data from six repeated cross-sectional studies in the population based Tromsø Study 1979-2016. Measured body height in cm and self-reported educational level were the primary outcome measures. We included 31 466 women and men aged 30-49 years, born between 1930 and 1977. Participants were stratified by 10-year birth cohorts and allocated into four groups based on attained levels of education. Descriptive statistics was used to estimate mean body height and calculate height differences between groups with different educational levels.

RESULTS

Mean body height increased by 3.4 cm (95% confidence interval (CI) 3.0, 3.8) in women (162.5-165.9 cm) and men (175.9-179.3 cm) between 1930 and 1977. The height difference between groups with primary education compared to long tertiary education was 5.1 cm (95% CI 3.7, 6.5) in women (161.6-166.7 cm) and 4.3 cm (95% CI 3.3, 5.3) in men (175.0-179.3 cm) born in 1930-39. The height differences between these educational groups were reduced to 3.0 cm (95% CI 1.9, 4.1) in women (163.6-166.6 cm) and 2.0 cm (95% CI 0.9, 3.1) in men (178.3-180.3 cm) born in 1970-77.

CONCLUSIONS

Body height increased in women and men. Women and men with long tertiary education had the highest mean body height, which remained stable across all birth cohorts. Women and men in the three other groups had a gradual increase in height by birth cohort, reducing overall height differences between educational groups in our study population.

An increase in the developmental tempo affects the secular trend in height in male Austrian conscripts birth cohorts 1951-2002

OBJECTIVES

Using population-based data on height in Austria from birth cohort 1951 to 2002, we aim to evaluate the secular trends in height and developmental tempo among Austrian young men.

METHODS

Data were obtained from the Austrian conscription medical examination. We included 1 205 112 conscripts (18-<20 years) who were born between 1951 and 2002 and 853 645 conscripts (17-<19 years) who were born between 1961 and 2002. Height was measured during the medical examination and was used to evaluate the secular trends of mean height over time. Furthermore, the mean difference in height between conscripts of 17- and 18 years old were compared across birth cohorts.

RESULTS

The mean height of conscripts aged 17 years increased by 2.2 cm (p < .0001) in between 1961 and 2002. The mean height of conscripts aged 18 years increased by 4.3 cm (p < .0001) between 1951 and 2002. However, the increase in mean height has slowed down since the 1970 s. The difference in mean height between 17 and 18 years old widened from about 0.1 cm in 1961 to 0.3 cm around 1970 and then steadily narrowed again to 0.1 cm at the end of the study period.

CONCLUSIONS

The increasing trend in height slows at the end of the 20th century, the developmental tempo at the population level, however, continued to increase. The difference in mean height between 17 and 18 years old narrowed, which may indicate that young men reached their final height earlier.

Height of Male Prisoners in Santiago de Chile during the Nitrate Era: The Penalty of being Unskilled, Illiterate, Illegitimate and Mapuche

This article contributes to the study of inequality in the biological welfare of Chile’s adult population during the nitrate era, ca. 1880s–1930s, and in particular focuses on the impact of socioeconomic variables on height, making use of a sample of over 20,000 male inmates of the capital’s main jail. It shows that inmates with a university degree were taller than the rest; that those born legitimate were taller in adulthood; that those (Chilean born) whose surnames were Northern European were also taller than the rest, and in particular than those with Mapuche background; and that those able to read and write were also taller than illiterate inmates. Conditional regression analysis, examining both correlates at the mean and correlates across the height distribution, supports these findings. We show that there was more height inequality in the population according to socioeconomic status and human capital than previously thought, while also confirming the importance of socioeconomic influences during childhood on physical growth.

Empirical comparisons of multiple Mendelian randomization approaches in the presence of assortative mating

BACKGROUND

Mendelian randomization (MR) is widely used to unravel causal relationships in epidemiological studies. Whereas multiple MR methods have been developed to control for bias due to horizontal pleiotropy, their performance in the presence of other sources of bias, like non-random mating, has been mostly evaluated using simulated data. Empirical comparisons of MR estimators in such scenarios have yet to be conducted. Pleiotropy and non-random mating have been shown to account equally for the genetic correlation between height and educational attainment. Previous studies probing the causal nature of this association have produced conflicting results.

METHODS

We estimated the causal effect of height on educational attainment in various MR models, including the MR-Egger and the MR-Direction of Causation (MR-DoC) models that correct for, or explicitly model, horizontal pleiotropy.

RESULTS

We reproduced the weak but positive association between height and education in the Netherlands Twin Register sample (P= 3.9 × 10-6). All MR analyses suggested that height has a robust, albeit small, causal effect on education. We showed via simulations that potential assortment for height and education had no effect on the causal parameter in the MR-DoC model. With the pleiotropic effect freely estimated, MR-DoC yielded a null finding.

CONCLUSIONS

Non-random mating may have a bearing on the results of MR studies based on unrelated individuals. Family data enable tests of causal relationships to be conducted more rigorously, and are recommended to triangulate results of MR studies assessing pairs of traits leading to non-random mate selection.

Social class-specific secular trends in height among 19-year old Polish men: 6th national surveys from 1965 till 2010

The results presented in this study concern the assessment of the secular trend of body height in 10 % a random national sample (N = 134,224) representing all regions of Poland in 8 homogeneous social groups over 45 years in Poland (1965-2010). Very significant political, social and economic changes in Poland occurred in the period studied. The political revolution that began in Poland at the turn of the 1980s and 1990s dramatically changed the picture of social inequalities in the country. It rapidly transformed (in different directions and to a different degree) the economic situation, working conditions, lifestyles and the prestige of particular social classes and professional groups. A positive secular trend was observed in 19-year-old participants in the period analysed in all homogeneous socio-professional groups, however, with different intensity in each group. The highest body height increases in 1965-2010 were observed in the sons of farmers with post-primary father's education (7.77 cm). The lowest were observed among the sons of professionals, only 5.45 cm. Although social distances between extreme socio-economic groups significantly decreased (from 4.89 cm in 1965 to 2.76 cm in 2010), social gradients of body height, despite the improvement in the standards of living of the entire society remained exceptionally stable and unchanged for nearly half a century.

Gender inequality and sexual height dimorphism in Chile

Chile has experienced significant improvements in its economy; thus, a secular trend in height has been observed in its population. Gender equality has also improved hand in hand with active policies addressing the gender gap in several dimensions (work, education, health) and overall economic improvement. This study examined changes in sexual height dimorphism in four samples of Chilean male and female working-age subjects and attempted to establish associations with gender equality and welfare. Sexual height dimorphism was calculated and compared with gender equality and overall welfare indicators between 1955 and 1995. Sexual height dimorphism reduction was seen to be strongly associated with greater gender equality and some general welfare indicators, such as the infant mortality rate. Gross domestic product per capita was not associated with sexual height dimorphism, but it showed significant associations with gender equality indicators. Overall, the gender gap has been reduced in Chile, which can be observed through improvements in gender equality indicators and a reduction in height dimorphism, mainly in areas associated with women's health. However, gender equality is still far behind in terms of female labour participation and women in political power, which require attention and further improvements.

Morphometric traits predict educational attainment independently of socioeconomic background

Background

Aim of this study is to describe the relationship between anthropometric traits and educational attainment among Estonian schoolchildren born between 1937 and 1962. We asked whether height, cranial volume and face width (a testosterone-dependent trait), measured in childhood predict later educational attainment independently of each other, family socioeconomic position (SEP) and sex. Associations between morphometric traits and education and their interactions with biosocial variables are of scholarly importance because higher education is nearly universally associated with low fertility in women, and often with high fertility in men. Hence, morphometric traits associated with educational attainment are targeted by natural selection and describing the exact nature of these associations is relevant for understanding the current patterns of evolution of human body size.

Methods

Data on morphometric measurements and family background of 11,032 Estonian schoolchildren measured between seven and 19 years of age were obtained from the study performed by Juhan Aul between 1956 and 1969. Ordinal logistic regression was used for testing the effects of morphometric traits, biosocial variables and their interaction on the cumulative probability of obtaining education beyond primary level.

Results

Of biosocial variables, family SEP was the most important determinant of educational attainment, followed by the sex, rural vs urban origin and the number of siblings. No significant interactions with morphometric traits were detected, i.e., within each category of SEP, rural vs urban origin and sex, taller children and those with larger heads and relatively narrower faces were more likely to proceed to secondary and/or tertiary education. The effect of height on education was independent of cranial volume, indicating that taller children did not obtain more educations because their brains were larger than those of shorter children; height per se was important.

Conclusions

Our main finding – that adjusting for other morphometric traits and biosocial variables, morphometric traits still robustly predicted educational attainment, is relevant for understanding the current patterns of evolution of human body size. Our findings suggest that fecundity selection acting on educational attainment could be partly responsible for the concurrent selection for smaller stature and cranial volume in women and opposite trends in men.

Educational level and its relationship with body height and popliteal height in Chilean male workers

A secular trend in body height has been experienced in many nations and populations, hypothesized to be the result of better living conditions. Educational level has been shown to be closely associated with body height. This study examined the changes in body height and popliteal height in a group of adult Chilean male workers by age cohort and the relationship of these with educational level. The body heights and popliteal heights of 1404 male workers from the Valparaíso and Metropolitan regions of Chile were measured in 2016. The sample was grouped by level of education (primary, secondary, technical and university) and age (21-30, 31-40 and 41-50 years). Robust ANOVA and post-hoc analyses using a one-step modified M-estimation of location were conducted based on bootstrap resampling. Both body height and popliteal height increased from the older to the younger age cohort. The largest increase was from the 41-50 to the 21-30 group, with a 1.1% increase in body height and 1.7% increase in popliteal height. When educational level was introduced into the analysis there was a marked increase in both body height and popliteal height for each cohort, but only in primary- and secondary-educated workers. Despite showing an overall increase in body height and popliteal height, younger workers with the highest levels of education showed fewer differences between them than did older workers with less education. The differences were larger in the older than in the younger cohorts. Similarly, this trend was less clear in workers with higher levels of education (technical and university), probably because of a dilution effect caused by increased access to higher education by workers in the lower income quintiles.

Talented but lazy. The height-school premium among Cracow's schoolboys in the interwar period

This study finds that a positive association between stature and academic performance measured by the grades for various subjects, the height-school premium, was present in a historical sample of 147 school boys attending a gymnasium (public secondary school) in Cracow, Poland, between the wars. This effect persists when controlling for a set of demographic and socio-economic variables, though the strength of the relationship is modest (0.018 higher average grade for Polish, 0.014 for mathematics, 0.016 for art, and 0.013 for the combined subjects with each centimetre of height). The differences found between the magnitude and significance of the height-premium in different school subjects could be a marker of unequal association between stature, and cognitive, social, and physical skills, suggesting at least a partial role of cognitive ability in this relationship. However, the effect visible at the school level is not consistent between different teachers of the same subjects, hence the mechanism behind the height-school premium in the analysed population to a large extent relied on the subjective judgment of the teachers, who could reward social skills but also discriminate against shorter students.

Stature and education among Roma women: taller stature is associated with better educational and economic outcomes

The association between body height and educational outcome, as measured by years of completed schooling, was investigated among Roma women in Serbia in 2014-2018. Height, demographic data, level of schooling and reproductive histories were collected from 691 Roma women aged between 16 and 80 years living in rural settlements in central and western Serbia. Multinomial logistic regression analysis showed that short stature was associated with an increased risk of low education, possibly as a result of poor growth and developmental disadvantage in early life. Roma cultural practices were also shown to influence the school achievement of these Roma girls: in addition to height, education was positively associated with a higher bride price and better socioeconomic status, as acquired through marriage. For Roma women, height might influence not only their level of education but also their lifetime prospects.

Anthropometric characteristics of Chilean workers for ergonomic and design purposes

Obtaining an appropriate match between a product and its end-users requires anthropometric data, which are typically outdated and show variations among different countries. Chile had its anthropometric data taken nearly 20 years ago, thus they are probably outdated. The purpose of this article is to describe some anthropometric characteristics of Chilean workers. An anthropometric survey involving 27 measures and five calculated body dimensions was conducted in 2016. The measurements were based on ISO 7250 and ISO 15535 to ensure the highest standards possible, and a total of 2946 workers, aged from 18 to 76 years old, participated in the survey. The results showed that Chilean workers have smaller dimensions than Dutch and US workers but have larger dimensions than South Koreans. The data presented in this article constitute the most up-to-date anthropometric dataset describing the dimensions of Chilean workers. Practitioner Summary: In Chile, women are smaller and weigh less than men, and both of these populations have high body mass index (BMIs). In addition, the Chilean population exhibits substantial differences compared with other international adult populations. The data presented in this article should be used as a reference when designing for Chilean workers.

A tall order: Small area mapping and modelling of adult height among Swiss male conscripts

Adult height reflects an individual's socio-economic background and offers insights into the well-being of populations. Height is linked to various health outcomes such as morbidity and mortality and has consequences on the societal level. The aim of this study was to describe small-area variation of height and associated factors among young men in Switzerland. Data from 175,916 conscripts (aged between 18.50 and 20.50 years) was collected between 2005 and 2011, which represented approximately 90% of the corresponding birth cohorts. These were analysed using Gaussian hierarchical models in a Bayesian framework to investigate the spatial pattern of mean height across postcodes. The models varied both in random effects and degree of adjustment (professional status, area-based socioeconomic position, and language region). We found a strong spatial structure for mean height across postcodes. The range of height differences between mean postcode level estimates was 3.40cm according to the best fitting model, with the shorter conscripts coming from the Italian and French speaking parts of Switzerland. There were positive socioeconomic gradients in height at both individual and area-based levels. Spatial patterns for height persisted after adjustment for individual factors, but not when language region was included. Socio-economic position and cultural/natural boundaries such as language borders and mountain passes are shaping patterns of height for Swiss conscripts. Small area mapping of height contributes to the understanding of its cofactors.

The heights of French-Canadian convicts, 1780s-1820s

This paper uses a novel dataset of heights collected from the records of the Quebec City prison between 1813 and 1847 to survey the French-Canadian population of Quebec-which was then known either as Lower Canada or Canada East. Using a birth-cohort approach with 10year birth cohorts from the 1780s to the 1820s, we find that French-Canadian prisoners grew shorter over the period. Through the whole sample period, they were short compared to Americans. However, French-Canadians were taller either than their cousins in France or the inhabitants of Latin America (except Argentinians). In addition to extending anthropometric data in Canada to the 1780s, we are able to extend comparisons between the Old and New Worlds as well as comparisons between North America and Latin America. We highlight the key structural economic changes and shocks and discuss their possible impact on the anthropometric data.

Economics, human biology and inequality: A review of "puzzles" and recent contributions from a Deatonian perspective

The Nobel laureate Angus Deaton concentrated his work on puzzling developments and phenomena in economics. Puzzles are exciting elements in economics, because readers feel challenged by the question of how they can be solved. Among the puzzles analyzed by Deaton are: (1) Mortality increase of white, U.S. non-Hispanic men (2000 to today); (2) Why are height and income sometimes closely correlated, but not always?; (3) Height inequality among males and females; and (4) The Indian puzzle of declining consumption of calories during overall expenditure growth. This article reviews these "puzzles" and the main insights that Deaton derived from their discussion insofar as they pertain to the biological aspects of human development. I will focus on the field of this journal, Economics and Human Biology, in which Deaton has been very active over the last two decades. I will also document some of the responses by other scholars and their contributions to these puzzles, as they relate to the field of economics and human biology.

Pubertal Stress and Nutrition and their Association with Sexual Orientation and Height in the Add Health Data

A number of studies have indicated that gay men tend to be shorter, on average, than heterosexual men. Less evidence exists that lesbian women are taller, on average, than heterosexual women. The most popular explanation of the association between sexual orientation and height involves prenatal factors, such that, for example, gay men may have been exposed to lower than typical androgens during fetal development, which impacts their height and sexual orientation as adults. An alternative explanation involves stress, given that stress has been associated with sexual minority identification and with lower height. Another alternative explanation involves nutrition, although its relationship is less clear with sexual minority identification. Using the Add Health data, which is a large, nationally representative and longitudinal sample of American adolescents (n = 14,786), we tested a mediation model, such that sexual orientation → pubertal stress/nutrition → height. Within men, we found that gay men (n = 126) were shorter, on average, than heterosexual men (n = 6412). None of the 24 pubertal stress-related and 15 pubertal nutrition-related variables assessed in the Add Health data mediated the relationship between sexual orientation and height in men. Within women, lesbians (n = 75) did not differ significantly in stature compared to heterosexual women (n = 6267). Thus, prenatal mechanisms (e.g., hormones, maternal immune response) are likely better candidates for explaining the height difference between gay men and heterosexual men.

Healthy(?), wealthy, and wise: Birth order and adult health

While recent research has found that birth order affects outcomes such as education and earnings, the evidence for effects on health is more limited. This paper uses a large Norwegian dataset to focus on the relationship between birth order and a range of health and health-related behaviors, outcomes not previously available in datasets of this magnitude. Interestingly, we find complicated effects of birth order. First-borns are more likely to be overweight, to be obese, and to have high blood pressure and high triglycerides. For example, compared to fifth-borns, first-borns are about 5% points more likely to be obese and 7% points more likely to have high blood pressure. So, unlike education or earnings, there is no clear first-born advantage in health. However, first-borns are about 13% points less likely to smoke daily than fifth-borns and are more likely to report good physical and mental health. Later-borns also score lower on well-being with fifth-borns being about 9% points less likely than first-borns to report that they are happy. Our findings are generally monotonic with middle-borns having outcomes that are intermediate between first- and fifth-borns. We find that these effects are largely unaffected by conditioning on education and earnings, suggesting that these are not the only important pathways to health differentials by birth order. When we explore possible mechanisms, we find that early maternal investment may play a role in birth order effects on health.

Can resource dilution explain differences in height by birth order and family size? A study of 389,287 male recruits in twentieth-century Netherlands

'Resource dilution' has been invoked as a possible mechanism to explain the inverse relation between sibship size and sibling heights in European populations (Öberg, 2015). Alternative explanations include confounding of the relation by other measured or unmeasured family characteristics including socio-economic position or birth order. It is difficult to quantify the contribution of any factor in isolation. To examine the question, we accessed data from the national birth cohort of 389,287 Dutch conscripts born in 1944-1947 and examined for military service at age 18. The records include all men of Dutch nationality born between January 1, 1944 and December 31, 1947 examined for military service in the Netherlands. The birth cohorts provide a well-defined study population to reliably assess the impact of family size and birth order on adult height, accounting for potential confounders. The cohorts include a large number of high-parity families, provide reliable information on both family size and birth order, and differentiate between all birth orders. The military examinations provide reliable information on height for all study subjects and uniform measurements at age 18. We show that recruits from larger families are shorter than recruits from smaller families; that birth order effects are small in relation to family size effects; and that birth order and family size effects are comparable in recruits from higher to lower socio-economic backgrounds. Recruits from higher backgrounds are significantly taller however. Our findings are compatible with a 'resource dilution' hypothesis, but our data provide no information on any specific differences in the childhood environment in terms of nutrition, education, or other family behaviours could explain the observed height differences at age 18. Additional studies will be needed to identify what differences in specific family behaviours could lead to changes in height development.

Adult Body Height Is a Good Predictor of Different Dimensions of Cognitive Function in Aged Individuals: A Cross-Sectional Study

Background: Adult height, weight, and adiposity measures have been suggested by some studies to be predictors of depression, cognitive impairment, and dementia. However, the presence of confounding factors and the lack of a thorough neuropsychological evaluation in many of these studies have precluded a definitive conclusion about the influence of anthropometric measures in cognition and depression. In this study we aimed to assess the value of height, weight, and abdominal perimeter to predict cognitive impairment and depressive symptoms in aged individuals.

Methods and Findings: Cross-sectional study performed between 2010 and 2012 in the Portuguese general community. A total of 1050 participants were included in the study and randomly selected from local area health authority registries. The cohort was representative of the general Portuguese population with respect to age (above 50 years of age) and gender. Cognitive function was assessed using a battery of tests grouped in two dimensions: general executive function and memory. Two-step hierarchical multiple linear regression models were conducted to determine the predictive value of anthropometric measures in cognitive performance and mood before and after correction for possible confounding factors (gender, age, school years, physical activity, alcohol consumption, and smoking habits). We found single associations of weight, height, body mass index, abdominal perimeter, and age with executive function, memory and depressive symptoms. However, when included in a predictive model adjusted for gender, age, school years, and lifestyle factors only height prevailed as a significant predictor of general executive function (β = 0.139; p < 0.001) and memory (β = 0.099; p < 0.05). No relation was found between mood and any of the anthropometric measures studied.

Conclusions and Relevance: Height is an independent predictor of cognitive function in late-life and its effects on the general and executive function and memory are independent of age, weight, education level, gender, and lifestyle factors. Altogether, our data suggests that modulators of adult height during childhood may irreversibly contribute to cognitive function in adult life and that height should be used in models to predict cognitive performance.

Height of Northern Jordanian middle-class adults, born 1960-1990 in the response to improving socio-economic conditions

The purpose of this study is to document and explain secular trends in stature among Northern Jordanian men and women between the years of birth 1960 and 1990, as they relate to overall per capita socio-economic improvement, the stature of 360 adults from two Northern governorates, those of Jerash and Irbid, was measured. General linear model (GLM) was used to examine the effect of birth-decade, education level of subject, and their interaction on mean stature of each sex separately. GLM results revealed that women who were born during the following three decades pooled together (1951-1980) did not differ significantly in mean stature from those born during (1981-1990). Among men, stature of those born in the two pooled birth-decades together (1951-1970) did not significantly differ of those were born in the two pooled birth-decades (1971-1990).