Spss statistics software version 26.0 for windows

Data analysis was performed using IBM SPSS Statistics software version 26.0 for Windows (IBM Corp., Armonk, NY, United States). Descriptive and inferential statistics methodologies were applied. Furthermore, a principal component analysis (PCA) was performed to examine the factor structure of the questionnaire.
All of the items were distributed, according to the rotated component matrix, via Varimax, with Kaiser normalization methods. The obtained Kaiser–Meyer–Olkin (KMO) validity test value was 0.902, falling into the range between 0.8 and 1.0, that deems a sample adequate for factor analysis. The extraction and retention of factors were based on visual examination of the scree plot, and eigenvalues >1.0 were retained. Factor loadings approximately equal to or higher than 0.50 dictated the assignment to a certain component. For questions with similar scores, a decision was made upon the contextualization of the question within each component, thus making its assignment to each one of two components possible.

As reported by our institutional medical records, the incidence of nausea in patients who were administered dexamethasone and ondansetron while undergoing laparoscopic gynecologic surgery with sufentanil-based IV-PCA was 50%. The required number of patients for a 50% decrement in the incidence of PONV [15 (link),16 (link)] at 80% power, with a two-sided alpha error of 0.05, was 65 per group; thus, 144 patients were recruited, anticipating a dropout rate of 10%. The per-protocol approach was used to analyze the main results based on the data of the patients who completed this study. Statistical analyses were conducted with the SPSS Statistics software version 26.0 for Windows (IBM Corp, Armonk, NY, USA). For quantitative variables, normality was assessed using the Shapiro–Wilk test. The independent t-test or Wilcoxon test was used for the normally or non-normally distributed variables, respectively. For dichotomous variables, the χ² test or Fisher’s exact test was used. Data are displayed as median (interquartile range [IQR]), or the number of patients (%). A p-value of less than 0.05 is considered to be statistically significant.

All continuous variables followed a Gaussian distribution; therefore, they are presented as mean ± standard deviation (SD). Discrete variables are reported as frequencies and proportions. Descriptive characteristics were compared among chronotype groups using one-way ANOVA with Bonferroni post hoc test for numeric variables. The Χ² test was used to compare categorical variables.
The association of rMEQ score with the continuous outcomes of interest (WC, VAT, SAT, VAT/SAT ratio) was evaluated using pre-specified linear regression models and robust confidence intervals, including sex (discrete, 0 = female; 1 = male), age (continuous, years), BMI (continuous, kg/m²), and MED score (continuous, units) as confounders. A p-value < 0.05 was considered statistically significant. Statistical analysis was performed using IBM SPSS Statistics software version 26.0 for Windows (IBM, Armonk, NY, USA).