I have looked at this example however there is no guidance on how to change the reference category in e.g. sex from female to male or age from <40 years to any other category.
Could I please also ask if it is possible in any way to remove the reference category from the OR plot so for example if sex= female is the reference category, have only the OR and the box for sex= male in the plot.
If you type ?or_plot in to the console, you can see the documentation for the function. There is a remove_ref parameter, which by default is set to FALSE.