Table 1.

Training Set Sampling Categories

Patient category index	$R_{max}$ interval	Number of patients
0	$R_{max}=0$	189
1	$0<R_{max}\le 1$	208
2	$1<R_{max}\le 2$	42
3	$2<R_{max}\le 3$	29

Note: Random sampling across all categories would form a training set that consists primarily of patients with R _max≤1. In contrast, randomly selecting 15 patients from category 3, for example, guarantees that the training set will include 15 patients, with at least one bone that received a visual BME score greater than 2. Thus, random sampling from individual categories helps to ensure that T _C2 is optimized with respect to the entire range of the visual BME score.