Normal distribution of variables will be assessed with the Shapiro-Wilk test. Statistical significance will be assessed by the parametric Student's t-test or the non-parametric Mann-Whitney test, as appropriate. If necessary, the investigators will use Bonferroni correction for multiple comparisons. Categorical variables and percentile comparisons will be performed using a Chi-squared test or the Fisher's exact test, as appropriate. Two-sided p<0.05 will be considered statistically significant. Variables with statistically significant differences and clinically relevant variables will be regressed out against the in-hospital FNP by using a stepwise backwards multivariate logistic regression approach. The clinical-based model will be developed to predict FNP with the highest sensitivity and specificity achievable by using the minimum number of variables that guarantees the best performance and predictive accuracy.