Replacing the words "Experimental and Control " from the metanalysis with the words (postoperative and Preoperative)

I have run a metanalysis using the meta package and created the following forest plot. I want to replace the 2 words Experimental and Control with Postoperative and preoperative. How can I do that?

I have used the following code to create the forest plot

forest(MD_LYSHOLM,fixed = FALSE, random = TRUE, overall= FALSE, col.random = "blue", prediction = TRUE, pooled.events = TRUE, xlab = "Mean Difference in Lysholm Scores",fs.xlab = 14,weight.study = "random", col.study = "black", col.square = "red",col.square.lines = "black", col.diamond = "black",hetstat = TRUE, overall.hetstat = FALSE, hetlab = "Heterogeneity",resid.hetstat = FALSE, print.I2 = TRUE, print.tau = TRUE)

From the documentation, I found these function arguments

label.e
Label for experimental group.

label.c
Label for control group.

Edit your code to add these arguments in your call to metacont, which should follow over to forest. Alternatively you can specify them directly in your call to forest using the same arguments, i.e.

forest(
  MD_LYSHOLM,
  fixed = FALSE,
  random = TRUE,
  overall = FALSE,
  col.random = "blue",
  prediction = TRUE,
  pooled.events = TRUE,
  xlab = "Mean Difference in Lysholm Scores",
  fs.xlab = 14,
  weight.study = "random",
  col.study = "black",
  col.square = "red",
  col.square.lines = "black",
  col.diamond = "black",
  hetstat = TRUE,
  overall.hetstat = FALSE,
  hetlab = "Heterogeneity",
  resid.hetstat = FALSE,
  print.I2 = TRUE,
  print.tau = TRUE,
  label.c = "Pre-operative", # Added this
  label.e = "Post-operative" # Added this
)