Spss statistics for window version 26

Statistical analysis was performed using IBM SPSS Statistics for Window, Version 26.0 (IBM Corp., Armonk, NY, USA). Quantitative data (i.e., patient age and lesion size) are expressed as mean ± standard deviation and were compared by the Student’s t-test. The chi-squared test compared categorical variables. Univariate and multivariable logistic regression analyses were used successively to determine predictors for malignancy using Cohort 1. Once the predictive model was established, the regression coefficient (β), standard error (SE), the results of the hypothesis test commonly used for the regression coefficient (Wald χ²), and odds ratios (ORs) with their 95% confidence intervals (CIs) were recorded. The diagnostic performance of the predictive model and conventional US BI-RADS were assessed by plotting receiver operating characteristic (ROC) curves and assessing the areas under them (AUC). Sensitivity and specificity were calculated using ROC analysis. The best cutoff values were obtained using the Youden index (maximum sensitivity + specificity – 1). P values < 0.05 were considered statistically significant.

All statistical analyses were performed using SPSS Statistics for Window version 26.0 (IBM Corp, Armonk, NY). Descriptive statistics (mean and 95% confidence interval (CI) or frequency and percentage) were computed for all study variables. Mann-Whitney U tests were conducted to examine differences in anthropometric indicators, movement behaviors, motor skills and executive function between the sexes and residential settings. Chi-square tests or Fisher exact tests were used to examine differences in the proportion of children meeting the 24-h movement guidelines between the sexes. Wilcoxon-signed rank tests were used to examine changes in movement behaviors before and during COVID-19 period. Statistical significance was set at p < 0.05. All hypothesis testing should be treated as preliminary and treated with caution due to the study being underpowered.