@article{HermanussenSchefflerPulunganetal.2023, author = {Hermanussen, Michael and Scheffler, Christiane and Pulungan, Aman B. and Bandyopadhyay, Arup Ratan and Ghosh, Jyoti Ratan and {\"O}zdemir, Ay{\c{s}}eg{\"u}l and Koca {\"O}zer, Ba{\c{s}}ak and Musalek, Martin and Lebedeva, Lidia and Godina, Elena and Bogin, Barry and Tutkuviene, Janina and Budrytė, Milda and Gervickaite, Simona and Limony, Yehuda and Kirchengast, Sylvia and Buston, Peter and Groth, Detlef and R{\"o}sler, Antonia and Gasparatos, Nikolaos and Erofeev, Sergei and Novine, Masiar and Navazo, B{\´a}rbara and Dahinten, Silvia and Gomuła, Aleksandra and Nowak-Szczepańska, Natalia and Kozieł, Sławomir}, title = {Environment, social behavior, and growth}, series = {Human biology and public health}, volume = {1}, journal = {Human biology and public health}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {2748-9957}, doi = {10.52905/hbph2023.1.59}, pages = {14}, year = {2023}, abstract = {Twenty-four scientists met for the annual Auxological conference held at Krobielowice castle, Poland, to discuss the diverse influences of the environment and of social behavior on growth following last year's focus on growth and public health concerns (Hermanussen et al., 2022b). Growth and final body size exhibit marked plastic responses to ecological conditions. Among the shortest are the pygmoid people of Rampasasa, Flores, Indonesia, who still live under most secluded insular conditions. Genetics and nutrition are usually considered responsible for the poor growth in many parts of this world, but evidence is accumulating on the prominent impact of social embedding on child growth. Secular trends not only in the growth of height, but also in body proportions, accompany the secular changes in the social, economic and political conditions, with major influences on the emotional and educational circumstances under which the children grow up (Bogin, 2021). Aspects of developmental tempo and aspects of sports were discussed, and the impact of migration by the example of women from Bangladesh who grew up in the UK. Child growth was considered in particular from the point of view of strategic adjustments of individual size within the network of its social group. Theoretical considerations on network characteristics were presented and related to the evolutionary conservation of growth regulating hypothalamic neuropeptides that have been shown to link behavior and physical growth in the vertebrate species. New statistical approaches were presented for the evaluation of short term growth measurements that permit monitoring child growth at intervals of a few days and weeks.}, language = {en} } @article{GasparatosSchefflerHermanussen2023, author = {Gasparatos, Nikolaos and Scheffler, Christiane and Hermanussen, Michael}, title = {Assessing the applicability of changepoint analysis to analyse short-term growth}, series = {Human biology and public health}, volume = {1}, journal = {Human biology and public health}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {2748-9957}, doi = {10.52905/hbph2023.1.62}, pages = {15}, year = {2023}, abstract = {Background: Assessing short-term growth in humans is still fraught with difficulties. Especially when looking for small variations and increments, such as mini growth spurts, high precision instruments or frequent measurements are necessary. Daily measurements however require a lot of effort, both for anthropologists and for the subjects. Therefore, new sophisticated approaches are needed that reduce fluctuations and reveal underlying patterns. Objectives: Changepoints are abrupt variations in the properties of time series data. In the context of growth, such variations could be variation in mean height. By adjusting the variance and using different growth models, we assessed the ability of changepoint analysis to analyse short-term growth and detect mini growth spurts. Sample and Methods: We performed Bayesian changepoint analysis on simulated growth data using the bcp package in R. Simulated growth patterns included stasis, linear growth, catch-up growth, and mini growth spurts. Specificity and a normalised variant of the Matthews correlation coefficient (MCC) were used to assess the algorithm's performance. Welch's t-test was used to compare differences of the mean. Results: First results show that changepoint analysis can detect mini growth spurts. However, the ability to detect mini growth spurts is highly dependent on measurement error. Data preparation, such as ranking and rotating time series data, showed negligible improvements. Missing data was an issue and may affect the prediction quality of the classification metrics. Conclusion: Changepoint analysis is a promising tool to analyse short-term growth. However, further optimisation and analysis of real growth data is needed to make broader generalisations.}, language = {en} } @article{GrothSchefflerHermanussen2023, author = {Groth, Detlef and Scheffler, Christiane and Hermanussen, Michael}, title = {Human growth data analysis and statistics - the 5th G{\"u}lpe International Student Summer School}, series = {Human biology and public health}, volume = {1}, journal = {Human biology and public health}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {2748-9957}, doi = {10.52905/hbph2023.1.70}, pages = {5}, year = {2023}, abstract = {The Summer School in G{\"u}lpe (Ecological Station of the University of Potsdam) offers an exceptional learning opportunity for students to apply their knowledge and skills to real-world problems. With the guidance of experienced human biologists, statisticians, and programmers, students have the unique chance to analyze their own data and gain valuable insights. This interdisciplinary setting not only bridges different research areas but also leads to highly valuable outputs. The progress of students within just a few days is truly remarkable, especially when they are motivated and receive immediate feedback on their questions, problems, and results. The Summer School covers a wide range of topics, with this year's focus mainly on two areas: understanding the impact of socioeconomic and physiological factors on human development and mastering statistical techniques for analyzing data such as changepoint analysis and the St. Nicolas House Analysis (SNHA) to visualize interacting variables. The latter technique, born out of the Summer School's emphasis on gaining comprehensive data insights and understanding major relationships, has proven to be a valuable tool for researchers in the field. The articles in this special issue demonstrate that the Summer School in G{\"u}lpe stands as a testament to the power of practical learning and collaboration. Students who attend not only gain hands-on experience but also benefit from the expertise of professionals and the opportunity to engage with peers from diverse disciplines.}, language = {en} } @article{RoeslerSchefflerHermanussen2023, author = {R{\"o}sler, Antonia and Scheffler, Christiane and Hermanussen, Michael}, title = {No evidence of growth impairment after forced migration in Polish school children after World War II}, series = {Human biology and public health}, volume = {1}, journal = {Human biology and public health}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {2748-9957}, doi = {10.52905/hbph2023.1.68}, pages = {8}, year = {2023}, abstract = {Background: Migration is omnipresent. It can come hand in hand with emotional stress which is known to influence the growth of children. Objective: The aim of this study was to analyse whether type of migration (forced or voluntary) and the geographic direction had influenced the growth of Polish children after World War II. Sample and Methods: A sub dataset of 2,208 individuals between the ages of 2-20, created from data of the 2nd Polish Anthropological Survey carried out in 1966-1969, including anthropometrical data and social and demographic information based on questionnaire, was used to analyse migration effects. Results: No association could be found between the direction of migration and the height of the children. The confidence intervals of the means of all classified migration categories overlap significantly and the effect size of the influence of migration category on height is ds=.140, which is too low to see any effects, even if there were one. Conclusion: Neither forced nor voluntary migration in Poland after World War II led to a change in height in children of migrating families.}, language = {en} } @article{HermanussenScheffler2023, author = {Hermanussen, Michael and Scheffler, Christiane}, title = {Nutrition, size, and tempo}, series = {Human biology and public health}, volume = {2022}, journal = {Human biology and public health}, number = {3}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {2748-9957}, doi = {10.52905/hbph2022.3.37}, pages = {11}, year = {2023}, abstract = {Nutrition is a prerequisite, but not a regulator of growth. Growth is defined as increase in size over time. The understanding of growth includes an understanding of the binary concept of physical time and individual tempo. Excess food causes tempo acceleration. Food restriction delays tempo. Tempo reflects the pace of life. It is a dynamic physical response to a broad spectrum of social, economic, political, and emotional (SEPE) factors and can affect life expectancy. Variations in tempo create distortions of the z-score patterns of height and weight. Illness or intermediate food shortage lead to intermediate halts in development and create short dips in the z-score patterns. Children who develop throughout life at delayed pace usually run at lower z-scores for height and weight, and show a characteristic adolescent trough; children who develop throughout life at faster than average pace usually run at higher z-scores and show a characteristic adolescent peak in their z-score patterns. During adolescence, almost half of the height variance is due to tempo variation. There is not one tempo for the whole body. Different organ systems grow and mature at different pace.}, language = {en} } @article{SchefflerHermanussen2023, author = {Scheffler, Christiane and Hermanussen, Michael}, title = {What does stunting tell us?}, series = {Human biology and public health}, volume = {2022}, journal = {Human biology and public health}, number = {3}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {2748-9957}, doi = {10.52905/hbph2022.3.36}, pages = {1 -- 15}, year = {2023}, abstract = {Stunting is commonly linked with undernutrition. Yet, already after World War I, German pediatricians questioned this link and stated that no association exists between nutrition and height. Recent analyses within different populations of Low- and middle-income countries with high rates of stunted children failed to support the assumption that stunted children have a low BMI and skinfold sickness as signs of severe caloric deficiency. So, stunting is not a synonym of malnutrition. Parental education level has a positive influence on body height in stunted populations, e.g., in India and in Indonesia. Socially disadvantaged children tend to be shorter and lighter than children from affluent families. Humans are social mammals; they regulate growth similar to other social mammals. Also in humans, body height is strongly associated with the position within the social hierarchy, reflecting the personal and group-specific social, economic, political, and emotional environment. These non-nutritional impact factors on growth are summarized by the concept of SEPE (Social-Economic-Political-Emotional) factors. SEPE reflects on prestige, dominance-subordination, social identity, and ego motivation of individuals and social groups.}, language = {en} } @article{MummSchefflerHermanussen2022, author = {Mumm, Rebekka and Scheffler, Christiane and Hermanussen, Michael}, title = {Locally structured correlation (LSC) plots describe inhomogeneity in normally distributed correlated bivariate variables}, series = {Archives of Public Health}, volume = {80}, journal = {Archives of Public Health}, publisher = {Springer Nature BMC}, address = {Bruxelles}, issn = {0778-7367}, doi = {10.1186/s13690-021-00748-4}, pages = {6}, year = {2022}, abstract = {Background The association between bivariate variables may not necessarily be homogeneous throughout the whole range of the variables. We present a new technique to describe inhomogeneity in the association of bivariate variables. Methods We consider the correlation of two normally distributed random variables. The 45° diagonal through the origin of coordinates represents the line on which all points would lie if the two variables completely agreed. If the two variables do not completely agree, the points will scatter on both sides of the diagonal and form a cloud. In case of a high association between the variables, the band width of this cloud will be narrow, in case of a low association, the band width will be wide. The band width directly relates to the magnitude of the correlation coefficient. We then determine the Euclidean distances between the diagonal and each point of the bivariate correlation, and rotate the coordinate system clockwise by 45°. The standard deviation of all Euclidean distances, named "global standard deviation", reflects the band width of all points along the former diagonal. Calculating moving averages of the standard deviation along the former diagonal results in "locally structured standard deviations" and reflect patterns of "locally structured correlations (LSC)". LSC highlight inhomogeneity of bivariate correlations. We exemplify this technique by analyzing the association between body mass index (BMI) and hip circumference (HC) in 6313 healthy East German adults aged 18 to 70 years. Results The correlation between BMI and HC in healthy adults is not homogeneous. LSC is able to identify regions where the predictive power of the bivariate correlation between BMI and HC increases or decreases, and highlights in our example that slim people have a higher association between BMI and HC than obese people. Conclusion Locally structured correlations (LSC) identify regions of higher or lower than average correlation between two normally distributed variables.}, language = {en} } @article{RoeslerGasparatosHermanussenetal.2022, author = {R{\"o}sler, Antonia and Gasparatos, Nikolaos and Hermanussen, Michael and Scheffler, Christiane}, title = {Practicability and user-friendliness of height measurements by proof of concept APP using Augmented Reality, in 22 healthy children}, series = {Human biology and public health}, volume = {2022}, journal = {Human biology and public health}, number = {2}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {2748-9957}, doi = {10.52905/hbph2022.2.48}, pages = {9}, year = {2022}, abstract = {Background: Child growth is a dynamic process. When measured at short intervals, children's growth shows characteristic patterns that can be of great importance for clinical purposes. Objective: To study whether measuring height on a daily basis using an APP is practicable and user-friendly. Methods: Recruitment took place via Snowball Sampling. Thirteen out of 14 contacted families signed up for a study period of 12 weeks with altogether 22 healthy children aged 3 to 13 years (response rate 93\%). The study started with a visit to the family home for the setup of the measurement site, conventional height measuring and initial training of the new measurement process. Follow-up appointments were made at four, eight and 12 weeks. The children's height was measured at daily intervals at their family homes over a period of three months. Results: The parents altogether recorded 1704 height measurements and meticulously documented practicability and problems when using the device. A 93\% response rate in recruitment was achieved by maintaining a high motivation within the families. Contact with the principal investigator was permanently available, including open communication, personal training and attendance during the appointments at the family homes. Conclusion: Measuring height by photographic display is interesting for children and parents and can be used for height measurements at home. A positive response rate of 13 out of 14 families with altogether 22 children highlights feasible recruitment and the high convenience and user-friendliness of daily APP-supported height measurements. Daily APP measurements appear to be a promising new tool for longitudinal growth studies.}, language = {en} } @article{BoekerHermanussenScheffler2022, author = {Boeker, Sonja and Hermanussen, Michael and Scheffler, Christiane}, title = {Dental age is an independent marker of biological age}, series = {Human biology and public health}, volume = {2021}, journal = {Human biology and public health}, number = {3, Summer School Supplement}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {2748-9957}, doi = {10.52905/hbph2021.3.24}, pages = {9}, year = {2022}, abstract = {Background: Biological age markers are a crucial indicator whether children are decelerated in growth tempo. Skeletal maturation is the standard measure. Yet, it relies on exposing children to x-radiation. Dental eruption is a potential, but highly debated, radiation free alternative.  Objectives: We assess the interrelationship between dental eruption and other maturational markers. We hypothesize that dental age correlates with body height and skeletal age. We further evaluate how the three different variables behave in cohorts from differing social backgrounds. Sample and Method: Dental, skeletal and height data from the 1970s to 1990s from Guatemalan boys were converted into standard deviation scores, using external references for each measurement. The boys, aged between 7 and 12, derived from different social backgrounds (middle SES (N = 6529), low-middle SES (N = 736), low SES Ladino (N = 3653) and low SES Maya (N = 4587). Results: Dental age shows only a weak correlation with skeletal age (0.18) and height (0.2). The distinction between cohorts differs according to each of the three measurements. All cohorts differ significantly in height. In skeletal maturation, the middle SES cohort is significantly advanced compared to all other cohorts. The periodically malnourished cohorts of low SES Mayas and Ladinos are significantly delayed in dental maturation compared to the well-nourished low-middle and middle class Ladino children. Conclusion: Dental development is an independent system, that is regulated by different mechanisms than skeletal development and growth. Tooth eruption is sensitive to nutritional status, whereas skeletal age is more sensitive to socioeconomic background.}, language = {en} } @article{HermanussenGrothScheffler2022, author = {Hermanussen, Michael and Groth, Detlef and Scheffler, Christiane}, title = {Human growth data analyses and statistics}, series = {Human biology and public health}, volume = {2021}, journal = {Human biology and public health}, number = {3, Summer School Supplement}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {2748-9957}, doi = {10.52905/hbph2021.3.29}, pages = {4}, year = {2022}, abstract = {Students learn by repetition. Repetition is essential, but repetition needs questioning, and questioning the repertoire belongs to the essential tasks of student education. Guiding students to questioning was and is our prime motive to offer our International Student Summer Schools. The data were critically discussed among the students, in the twilight of Just So Stories, common knowledge, and prompted questioning of contemporary solutions. For these schools, the students bring their own data, carry their preliminary concepts, and in group discussions, they may have to challenge these concepts. Catch-up growth is known to affect long bone growth, but different opinions exist to what extent it also affects body proportions. Skeletal age and dental development are considered appropriate measures of maturation, but it appears that both system develop independently and are regulated by different mechanisms. Body weight distributions are assumed to be skewed, yet, historic data disproved this assumption. Many discussions focused on current ideas of global growth standards as a common yardstick for all populations world-wide, with new statistical tools being developed including network reconstruction and evaluation of the reconstructs to determine the confidence of graph prediction methods.}, language = {en} }