Figure 2
Pain thresholds data and basic statistical assessments. (A) Log10-transformed threshold to mechanical, electrical, or thermal noxious stimuli and the effects of hypersensitization by local application of capsaicin or menthol. Individual data points are presented as dots on violin plots showing the probability density distribution of the variables, overlaid with box plots where the boxes were constructed using the minimum, quartiles, median (solid line inside the box) and maximum of these values. The whiskers add 1.5 times the interquartile range (IQR) to the 75th percentile or subtract 1.5 times the IQR from the 25th percentile. At the top of the panels are the p values of the statistical comparisons for sex. (B) Direction and size of effect quantified using Cohen’s d. Because for cold stimuli higher threshold values mean higher pain sensitivity whereas for mechanical and heat stimuli, lower threshold values mean higher pain sensitivity, the direction of differences seems inconsistent. Therefore, the columns are colored for the direction of sex differences. (C) Correlation matrix of pain thresholds. Each cell is colored according to the correlation coefficient and labeled with the respective p value. The figure has been created using the R software package (version 4.2.2 for Linux; http://CRAN.R-project.org/6) and the R library "ggplot2" (https://cran.r-project.org/package=ggplot27).
