Figure 5.

Sample sizes refer to reports on AI and machine learning in pain research. Sample sizes were manually extracted from the summaries of the 475 queried reports. The figure shows the distribution of sample sizes as a count density plot, drawn with the default settings of the built-in kernel density function of the R library “ggplot2”, overlaid with a histogram with binning for each power of 10. The figure has been created using the software package R (version 4.2.0 for Linux; https://CRAN.R-project.org/)⁷³ and the library “ggplot2” (https://cran.r-project.org/package=ggplot2).⁹³