Statistical analysis
SECONDARY
The primary hypothesis was that IPUS-AVP would be superior to CVC for the primary endpoint. Primary and secondary endpoints were tested for superiority according to the intention-to-treat (ITT) principle. Two groups were considered for the main analysis: IPUS-AVP and CVC. Different sensitivity analyses were performed and specifically a comparison of secondary outcomes in patients successfully managed by one single route as a face-to-face comparison of IPUS-AVP and CVC routes. A pre-specified analysis was performed according to stratification by number of leads to be implanted (single- or dual-chamber device).Sample size calculation was based on a success rate of 95% in the IPUS-AVP group and 80% in the CVC group. These estimations were obtained from literature data.The normality of distribution of continuous variables was tested using the Shapiro–Wilk test. Continuous variables with normal distribution are presented as means ± standard deviation, and non-normally distributed variables are shown as medians with inter-quartile range or geometric means with 95% confidence interval (CI). Categorical variables are presented as counts and percentages. Endpoints were tested independently for differences between the two groups. Differences in categorical variables were assessed using the χAll tests were two-sided. All statistical analyses were performed using IBM SPSS Statistics for Windows version 26 (IBM Corp., Armonk, NY, USA).