Statistical analysis
SECONDARY
A previous study showed a 6.5% mean risk of an AF episode during a 1-day period and 16.7% mean risk of at least one AF episode during a 7-day period [Efficacy analysis was conducted on the full analysis set (FAS), which included all patients who met the inclusion criteria but not the exclusion criteria. Patients who did not wear their assigned device after randomization and those for whom no data were available after randomization were excluded from the FAS. We used an exact McNemar’s test in the main analysis of the primary endpoint. In other analyses of the primary endpoint, the detection rate and exact confidence interval (CI) were calculated for each device. For the secondary endpoints, we applied the same analysis to binary variables as to the primary endpoint. Descriptive statistics (mean, standard deviation, median, and interquartile range) were calculated for frequency variables in both groups, and the Wilcoxon rank sum test was used to compare the groups. The significance level of the statistical test was set at 0.05, and a two-sided test was performed. The confidence interval was set at 95%. In dropouts, statistical tests were conducted for binary variables (yes/no) by imputing “No” if the data were missing for both devices or for one device and “No” for the other device, and by imputing “Yes” if the data were “Yes” for one device and missing for the other device. Imputation and modeling for missing values were not implemented for other analyses.The safety analysis population included all patients except those for whom no data were available after randomization. The same analysis was performed as for the primary endpoint.All analyses were performed using SAS ver. 9.4 (SAS Institute Inc., Cary, NC, USA).