2.5. Statistical Analysis

Continuous variables are expressed as median (interquartile range [IQR]), and categorical variables are expressed as percentages. The Shapiro-Wilk test was used to verify a normal distribution. In group comparisons, the Mann-Whitney U test and Kruskal-Wallis test were performed for continuous variables, and the chi-squared test was used for categorical variables. Multivariate logistic regression analysis was performed, with the presence of HAD as the dependent variable and multiple continuous and categorical variables as independent variables. Age, sex, albumin level, haemoglobin level, duration of ventilator intubation, APACHE II score, CRRT, NPPV, delirium, length of stay in the ICU, and the day of walking onset that were significantly different in the univariate analysis were included as adjusted variables. The level of significance was set at p ˂ 0.05, and all statistical analyses were performed using IBM SPSS Statistics version 22 (IBM Corp., Armonk, NY, USA).