Fig. 1.

The decision tree shows the options offered to the subject and the possible outcome states. The four terminal nodes are as follows: arthroscopy was chosen and a tear was present (denoted as Rx+ Dx+); arthroscopy was chosen and no tear was present (denoted as Rx+ Dx); nonoperative treatment was chosen but there was a tear (denoted as Rx− Dx+); and nonoperative treatment was chosen and there was no tear (denoted as Rx− Dx−).