R statistical platform

All analyses were carried out using R statistical platform (https://www.r-project.org, accessed on 30 April 2022) in R-studio, version 1.4.1106. In quantitative variables, normality assumption was tested using chi-squared goodness-of-fit test. For normally distributed data, t-test and ANOVA were used to compare the means of two groups and multiple groups, respectively. Kruskal–Wallis (KW) test was used to compare the medians for non-normally distributed data. Mann–Whitney and Tukey’s HSD tests were applied as post hoc tests using Bonferroni correction method for multiple comparisons in the Kruskal–Wallis and ANOVA tests, respectively. For all statistical analyses, p-values < 0.05 were considered statistically significant.

All experiments were carried out in triplicate, and the data were expressed as the mean ± SD. Statistical analysis was conducted using R statistical platform (https://www.r-project.org (accessed on 30 November 2021)). Among R-packages used in data analysis and visualization are readxl, ggridges and boxplot. Kruskal–Wallis one-way analysis of variance on ranks was used to test the significance among different groups. p-value < 0.05 was considered to indicate statistically significant differences.

Continuous variables were expressed as median (interquartile range) and categorical variables as count (percentage). For all analyses, circulating levels of miRNAs were log-transformed. Levels of miRNAs were compared among several group of patients, namely AHF with or without history of CHF (respectively named acute decompensated HF—ADHF—or de novo AHF), acute dyspnea from non-cardiac origin (non-AHF) and stable CHF using first the Kruskal-Wallis test and then the pairwise Wilcoxon test using an adjusted p value according to the Holm method.[23 ]
The ability of miRNAs to discriminate dyspnea of cardiac from non-cardiac origin was studied using receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC).[24 (link), 25 (link)] Association of circulating levels of miRNAs with one-year outcome was assessed using the chi square test. To take into account a potential confounding effect of prognostic covariates, adjusted analyses were performed using logistic regression. The association between miR-423-5p and one-year mortality in the validation cohort was assessed using Kaplan Meier analyses.
Statistical analyses were performed using the R statistical platform (http://www.r-project.org/) and the SigmaPlot v12 software. A 2-sided p value < 0.05 was considered statistically significant.

All data are expressed as mean ± standard error of the mean. Statistical comparisons were performed using one-way ANOVA for parametric tests followed by Dunnett’s test or Kruskal–Wallis of variance for non-parametric tests followed by Steel’s test. Overall and median survival were determined using Kaplan-Meier analyses and log-rank testing of variance. Differences showing values of p < 0.05 were considered statistically significant, as represented by a ‘*’ sign, and p < 0.01 is represented as a ‘**’ sign on the graph. All analyses were performed using the R statistical platform (ver. 3.4.2; https://www.r-project.org/).