Statistical methods
We used R version 4.1 (R Foundation for Statistical Computing, Vienna, Austria) and the Facenetmeta package to perform the data meta-analysis.
The treatment effect on continuous outcomes was expressed as the mean difference (MD) with 95% CI. The treatment effect for dichotomous outcomes was expressed as an odds ratio (OR) with a 95% confidence interval (CI). The methods were ranked based on the frequentist analog of the surface under the cumulative ranking curve (SUCRA).13 The SUCRA assigns numbers ranging from 0 to 1 to each treatment. A higher SUCRA indicates a higher likelihood that a specific treatment is most suitable for the investigated outcome. Comparing the obtained SUCRA for different treatments permits the creation of a ranking among treatments. Where necessary, we converted the reported median and interquartile range to the estimated mean and standard deviation (SD) using the Hozo method.14
When multiple local anesthetic dosing regimens were employed in the same study for the same block, the means and standard deviations were combined.