Statsdirectversion 3

This was performed using IBM SPSS version 20 (IBM Corp, Armonk, NY) and StatsDirect
version 3.0.150 (StatsDirect Ltd, Altrincham, UK). A power calculation was undertaken and
to be 80% sure of detecting a 10 percentage points difference between fulcrum flexibility
(%) and traction flexibility (%) measurements, with a standard deviation of 2.0, at the 5%
significance level, 34 pairs of measurements would be required. Data was plotted and
tested for normality. Where data was normally distributed, paired comparisons were made
using paired t tests. The difference between the traction and the
fulcrum-bend flexibility rate was evaluated using Wilcoxon’s matched pairs signed ranks
test. Correlation between the traction and the fulcrum-bend flexibility rate was tested
using Spearman’s rank correlation. Agreement of the fulcrum bend angle, the traction
angle, and the postoperative angle was assessed using Bland-Altman analysis (Figure 1).^{6 (link)}

All statistical analyses were performed using the StatsDirect Version 3.0.150 software program (StatsDirect, Cheshire, UK). Regarding controlled studies in which the treatment efficacy was evaluated by comparing the percentage of patients with dyspeptic symptoms that improved or disappeared among a group receiving an actual agent with that in a group receiving a placebo, we assessed the effect of the agents by showing the pooled relative risk (PRR) with its 95% confidence interval (95% CI) and p value. The p values less than 0.05 were considered statistically significant.
The PRR was calculated after adding the newly searched controlled studies to the four double-blind randomized studies (7 -10 (link)) from our previous review (6 (link)). The PRR was calculated using the DerSimonian and Laird method. To quantify heterogeneity, I² was calculated. A value of 0% indicates no observed heterogeneity, and larger values show increasing heterogeneity (11 (link)). The PRR was less than 1 when dyspepsia symptoms were improved by treatment with true drugs. A bias assessment plot was used to assess the publication bias and selection bias.