Add and modify borders of a sripe (s) item of a forest plot object (fobj).
Passed to abline.
s_borders(fobj, item = NULL, bordernr = NULL, ...)a forest plot object of class 'fobj'
item to be modified, either a number or the name of the column in fobj$dat. If NULL (the default), all items of type 's' are affected
border to be modified, 1 (left) or 2 (right). If NULL (the default), all borders are affected.
options to be passed to abline
a forest plot object of class 'fobj'