Background: Whether differences exist in sexual attitudes, behaviors, and knowledge, attitudes, and practices (KAP) regarding HIV/AIDS, tuberculosis, and hepatitis B between only-child and non-only-child college students in China remains unclear. Methods: From 2019 through 2022, we recruited 33,944 first-year students of Jiangsu origin from 20 universities in Jiangsu Province using a multistage, stratified random sampling design. Data on sexual attitudes, behaviors, and infectious disease KAP were obtained through a structured, self-administered online questionnaire. Propensity-score matching (PSM) was used to compare outcomes between only-child and non-only-child students. Sensitivity analyses were conducted with propensity-score and logistic regression. Results: Overall, 19,525 students (58.96%) were only-children. After PSM, no significant differences were observed between groups across sexual attitudes and behaviors. The odds ratios (ORs) for only-child students, as compared with non-only-child students, were 1.03 (95% CI, 0.961.10) for approving premarital sex, 0.97 (95% CI, 0.911.03) for willingness to use condoms consistently, and 1.20 (95% CI, 0.931.55) for undergoing immediate HIV antibody testing if infection was suspected. The ORs for having engaged in sexual activity, first intercourse at 18 years or older, and consistent condom use were 1.02 (95% CI, 0.861.21), 0.93 (95% CI, 0.651.31), and 1.34 (95% CI, 0.961.87), respectively. No significant differences were found in the proportions of students with high knowledge levels or positive behaviors related to infectious diseases (OR, 0.97; 95% CI, 0.901.04; OR, 1.02; 95% CI, 0.951.10). However, only-child students were more likely to demonstrate positive attitudes toward infectious diseases (OR, 1.10; 95% CI, 1.021.19). Sensitivity analyses supported the robustness of these findings. Conclusions: Only-child and non-only-child college students in China show broadly similar sexual attitudes, behaviors, and infectious disease KAP, with only modest differences in attitudinal domains. Therefore, health education does not need to be individualized based on sibling status; instead, universal and standardized interventions should be prioritized for all college students.
The pattern of body height development is dynamic across all phases of the life cycle and varies by sex, ethnicity, and population. Stunting in children deviates from the concept of normal height development and the secular trend. This study aimed to compare the body height of children in West Papua with World Health Organization growth standards and to assess malnutrition, particularly stunting, among children aged 519 years. This cross-sectional study included 546 children, comprising 242 boys and 304 girls. We calculated the standard deviation score (SDS) for body height. Nutritional status was assessed using height-for-age z-scores (HAZ) and body mass index-for-age z-scores (BAZ). The density distribution of body height SDS was examined. Normality was tested using the Shapiro-Wilk test, and differences in body height were analyzed using the Wilcoxon test, with p < 0.05 considered statistically significant. The mean SDS for girls was higher than that for boys. There were significant differences in body height between children in West Papua and the WHO reference population (p < 0.05). The percentage of severely stunted children was higher in girls (2.96%) than in boys (0.82%). In contrast, the prevalence of stunting was higher in boys (15.16%) than in girls (5.92%). Some stunted children were also classified as normal weight, overweight, or obese. Our findings indicate that short stature may reflect a combination of biological, environmental, and nutritional influences. Therefore, the use of body height alone as a reference for determining malnutrition should be approached cautiously, with consideration of alternative approaches and the biocultural characteristics of the local community.
Sex estimation from skeletal remains is fundamental to forensic identification. The first rib demonstrates enhanced preservation through superior cortical density and protected positioning, yet population-specific standards for Thai populations remain absent. To establish the first sex estimation standards from first rib morphometry in Northeastern Thai populations and evaluate comparative performance of discriminant function analysis (DFA), binary logistic regression (BLR), support vector machine (SVM), and Random Forest (RF). Six hundred first ribs from 300 males and 300 females with mean age of 56.67 ± 13.88 years from documented skeletal collections were digitized using 3D scanning. Seven morphometric parameters were measured by two trained observers with inter-observer reliability assessment. Four classification models were developed and their performance compared through cross-validation and ROC analysis. Inter-observer reliability was excellent with intraclass correlation coefficients ranging from 0.992 to 0.999. All parameters demonstrated significant sexual dimorphism at p < 0.01 with Cohens d ranging from 0.57 to 1.38. Length from tubercle to rib head with d = 1.38, distance from tubercle to internal margin with d = 1.17, and weight with d = 0.94 showed strongest discrimination. Comparative analysis revealed overall accuracy ranging from 75.2% to 81.0%. Random Forest achieved highest performance with 81.0% accuracy and AUC of 0.867 alongside 4.6% sex disparity. BLR demonstrated 80.3% accuracy with perfect balance showing 0% disparity, while DFA yielded 80.2% with 2.3% disparity. SVM underperformed at 75.2% with substantial bias of 19.0% disparity. This study provides the first validated sex estimation standards for Thai first rib morphometry. Binary logistic regression emerges as optimal for forensic application, balancing 80.3% accuracy, perfect sex-specific performance, and methodological transparency essential for legal proceedings, despite Random Forests marginally superior discriminatory capacity.
Focusing on craniofacial bones, this study investigates morphological variation related to sexual dimorphism in order to deepen our understanding of human biological diversity and to provide new data from a contemporary reference sample. Accordingly, the research was guided by three objectives (i) identify the facial regions exhibiting the greatest sexual dimorphism using landmark-based geometric morphometric method; (ii) evaluate the reliability of discriminant models based on these dimorphic regions; and (iii) conduct exploratory analyses to assign sex classification probabilities to ancient subjects using the discriminant models derived from a contemporary reference sample. The reference sample comprised 44 skulls from subjects of known sex who died in 2024. The ancient sample included 4 skulls recovered from the Grotte de La Medecine (France), attributed to the chalcolithic period. Fourteen facial landmarks were digitized using 3DSlicer. Generalized Procrustes Analysis was performed to extract shape variables and standardized coordinates for statistical analysis. Thin-Plate Spline transformations quantified and visualized deformation amplitudes between the female and male shapes. Landmarks in the orbital showed the highest deformation amplitudes. Goodall F-test comparing male and female shapes across three facial regions revealed significant sexual dimorphism only in the orbital region and the global facial shape. Discriminant analysis demonstrated that the orbital region provided the highest classification accuracy (88.6%) compared to the global facial region (72.7%). The discriminant models yielded high probabilities of male and female sex classification for the ancient subjects. Using a reproducible method, comparable levels of accuracy to those reported in the scientific literature were achieved despite a relatively modest sample size. These findings further confirm the significant role of the orbital region in human craniofacial sexual dimorphism.
Background: To analyze the inequality and change trends in height of children and adolescents aged 718 years in different regions of China from 1985 to 2019. Methods: Data were extracted for the height of Chinese children and adolescents aged 718 years from eight Chinese National Surveys on Students Constitution and Health (CNSSCH) from 1985 to 2019. We calculated the urbanrural difference in height of children and adolescents and the height coefficient of variation of urban and rural children and adolescents each year. Results: We found that there are large differences in the height of children and adolescents between urban and rural areas, the eastern regions and western regions, Shanghai and Guizhou. From 1985 to 2019, the urbanrural difference in height for boys decreased from 4.24 cm to 1.76 cm and for girls from 3.72 cm to 1.45 cm and the urbanrural difference in height for boys and girls in the western regions was larger. From 1985 to 2019, there were also large height differences between the eastern regions and western regions, Shanghai and Guizhou, which were comparisons of the height differences between developed and undeveloped areas of China. Meanwhile, height inequalities were more serious in rural areas. Whether in the eastern regions and western regions, Shanghai and Guizhou, the height differences between peers were larger in rural areas than in urban areas. Conclusions: There were obvious height inequalities in China. Although the urbanrural differences have decreased, the height differences among regions at different economic levels have gradually increased, especially in rural areas. These differences should be taken seriously and relevant policies should be formulated to reduce height inequalities for children and adolescents in different regions.
