G power

The variables with a normal distribution are reported as means ± standard deviations (SD), and continuous variables with a non-normal distribution are reported as medians (interquartile ranges). ANOVA was used to compare continuous variables with a normal distribution between the groups, and Welch’s test was adopted when variance existed between the groups and the different time points. Analysis of variance for repeated measurements was applied for repeated measured variables between the groups and the different times. The homogeneity of variance was analyzed using Mauchly’s test of sphericity and corrected with the Greenhouse-Geisser test if variance existed. Differences in the concentrations of coagulation proteins between the groups measured at the same time points were analyzed using two-way ANOVA followed by the Bonferroni test. The Kruskal-Wallis H test was applied to continuous variables with a non-normal distribution. The Chi-squared or Fisher’s exact test was used to analyze categorical data. All reported P values were two sided, and P values less than 0.05 were considered significant. Missing data was less than 10% and was not replaced. Intention to treat analysis was used and analysis was performed with SPSS version 18 (IBM, Armonk, NY) and G-Power (version 3.1; Informer Technologies, Inc.).

Between May 2021 and July 2021, subjects were recruited from local senior centers through a recruitment notice in Seoul. A total of 72 older adults were screened, and then 58 were finally selected (Figure 1). The inclusion criteria were as follows: (1) over 65 years of age, (2) those who have experienced falls in the last six months, (3) those who ambulate independently without any assistance devices, and (4) those who understand a simple instruction as confirmed by the Korean version of Mini-Mental Status Examination (≥24). The exclusion criteria were as follows: (1) those who have any neurological, orthopedic, or psychological disorders, (2) those who have visual or auditory impairments, and (3) those who have not participated in any programs for improving balance in the last six months. Exclusion criteria were confirmed through self-report with a promise that subjects only report the truth. The criteria were in accordance with a previous study [16 ].
The number of subjects was calculated using G*Power (Informer Technologies, Dusseldorf, Germany) [17 (link)]. With reference to a previous study [16 ], the effect size was set at 1.23, the α error at a probability of 0.05, and the power at 0.95, resulting in a minimum of 19 subjects required for each group.

The success rate of radial artery puncture was 0.53 with ultrasound guidance [12 (link)], and the median nerve block can increase the cross-sectional area (nearly 3-fold) of the radial artery [26 (link)]. We assumed that the success rate would be improved with median nerve block by at least 50% in women with gestational hypertension. A one-tailed chi-squared test was performed, and we estimated that 88 patients were required to provide 80% power with a type I error probability of 0.05. Assuming that the follow-up loss rate was 5%, a total of 92 cases were needed. Analysis was computed using G-Power (version 3.1; Informer Technologies, Inc.).