Statistical analysis
hypoxia
HYPOXIA, OBESE
The sample size was calculated using PASS software (version 11.0, NCSS, LLC, Kaysville, UT, United States). The Two Independent Proportions procedure was used. Test results indicate a 32% incidence of hypoxia in mildly obese patients under sedation procedure; thus, 32% of patients in the capnography group were expected to develop hypoxia. P1 and P2 were calculated based on the assumption that capnography would achieve a reduction in the incidence of hypoxia from 32 to 15%. Given an α = 0.05 and a power of 80%, it was estimated that 108 patients per group would be required for the study. Assuming a dropout rate of 5%, a total of 228 patients would be needed.A blinded statistician performed statistical analysis using SPSS (version 25.0). Data are summarized as mean ± SD/median (IQR) for continuous data and as frequencies/percentages for categorical data. The standardized mean difference (SMD) was defined as the difference between the mean value of a covariate in one group and the corresponding mean value of a covariate in the other group, divided by the pooled standard deviation. When assessing the balance between groups, an SMD < 0.1 indicated a better balance and was considered as a small difference between the two groups. The incidence of hypoxia for the primary outcome was analyzed using Fisher’s exact test for categorical variables. Secondary outcomes were also analyzed with the use of Fisher’s exact test for categorical variables as well as Student’s t-test for continuous variables with a composite normal distribution. Statistical significance was set at 