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Methods for group comparisons using predicted probabilities and marginal effects on probabilities are developed for regression models for binary outcomes. Unlike approaches based on the comparison of regression coefficients across groups, the methods we propose are unaffected by the scalar identification of the coefficients and are expressed in the natural metric of the outcome probability. While we develop our approach using binary logit with two groups, we consider how our interpretive framework can be used with a broad class of regression models and can be extended to any number of groups. [ABSTRACT FROM AUTHOR]

Objectives: Sex is usually not estimated in skeletonized non‐adult individuals because sexual dimorphism is considered minimal before puberty. In 2017, a new approach based on the shape of the auricular surface was proposed, showing that this anatomic area of the ilium is dimorphic. This study tests the reproducibility and evaluates the accuracy of the method in a bigger sample. Materials and Methods: Thirty males and 31 females from the Lisbon Collection (1 day–18 years old) were analyzed by two researchers, one experienced, and the other without previous knowledge of the method. The sample was divided into three groups according to prepubertal and pubertal hormonal peaks (<2, 0–12, and 13–18 years old). Two metric variables (DE/AD and FI/CF ratios), two morphological features (Overall Morphology, OM and Morphology of the Retroauricular End of the Superior Demiface, MRS), and two formulae were tested based on the adequate results obtained in the original article. Results: Data shows a low interobserver error (ICC > 0.92; K > 0.74). Morphological features provide better results than the metrics (DE/AD = 77.05%; FI/CF = 73.77%; OM = 80.33%; MRS = 85.24%). The discriminant function correctly classified 86.66% of the males and the logistic regression, 83.33%. The method was equally reliable in 0–12 and 13–18 years‐old age groups and more accurate in males. The accuracy of most of the variables reached 100% for males under 2 years‐old, and the probabilities were higher than for older individuals. The percentages of correct estimations are not influenced by the age, year, and cause of death. Discussion: Despite the relatively small sample size, this study confirms the usefulness of the auricular surface for non‐adult sexual estimation, especially for those younger than 2 years old. Additional validation tests in documented individuals from other geographic regions are suggested. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study is to analyze the data obtained from a randomized trial on the prevention of influenza by gargling with green tea, which gave nonsignificant results based on frequentist approaches, by using Bayesian approaches. Methods: The posterior proportion, with 95% credible interval (CrI), of influenza in each group was calculated. The Bayesian index θ is the probability that a hypothesis is true. In this case, θ is the probability that the hypothesis that green tea gargling reduced influenza compared with water gargling is true. Univariate and multivariate logistic regression analyses were also performed by using the Markov chain Monte Carlo method. Results: The full analysis set included 747 participants. During the study period, influenza occurred in 44 participants (5.9%). The difference between the two independent binominal proportions was −0.019 (95% CrI, −0.054 to 0.015; θ = 0.87). The partial regression coefficients in the univariate analysis were −0.35 (95% CrI, −1.00 to 0.24) with use of a uniform prior and −0.34 (95% CrI, −0.96 to 0.27) with use of a Jeffreys prior. In the multivariate analysis, the values were −0.37 (95% CrI, −0.96 to 0.30) and −0.36 (95% CrI, −1.03 to 0.21), respectively. Conclusions: The difference between the two independent binominal proportions was less than 0, and θ was greater than 0.85. Therefore, green tea gargling may slightly reduce influenza compared with water gargling. This analysis suggests that green tea gargling can be an additional preventive measure for use with other pharmaceutical and nonpharmaceutical measures and indicates the need for additional studies to confirm the effect of green tea gargling. [ABSTRACT FROM AUTHOR]