Table 10. Techniques for BAA by ROI.

ROI	Techniques for BAA
Hand, Wrist	Fels Method: This method was proposed as a less subjective way to assess skeletal age. It considers ossification, radiopaque densities, bony projection, shape changes and fusion. It comprises 98 indicators of bone maturity, where 85 are categorical and are 13 continuous (epiphyseal and metaphyseal fusion ratios) [58].
	Skeleton Maturation Indicators by Fishman: It assesses the skeletal maturity based on the following indicators: width of the epiphysis compared to the diaphysis (third and fifth fingers), gapping of epiphysis (third and fifth fingers), fusion of epiphysis and diaphysis (third, fifth fingers and radius) and ossification of adductor sesamoid of the thumb [59].
Hand	Gilsanz and Ratib: This method consists of a digital hand atlas with reference images of 29 classes from the ages of 0 to 18 with an additional class to represent subjects older than 18. [60]
Wrist	Cameriere et al.: This is a quantitative method that proposes a mathematical formula based on the ratio of the carpal area and the total area of carpal bones and epiphyses of the radius and ulna [61].
Knee	O’Connor et al.: A method that proposes five stages of epiphyseal fusion for the femur, tibia and fibula bones. It uses the frontal and lateral radiograph image of the knee [62].
	Krammer et al.: A method that proposes five stages of epiphyseal fusion (from 1 to 5 of which stages 2 and 3 have 3 sub stages each) of the distal femur [63].
Clavicle	Schmeling et al.: This method defines 5 stages of ossification of the medial clavicular epiphysis [64].
	Kreitner et al.: This method is similar to the one proposed by Schmeling et al. (63), but instead of 5 stages there are 4, and the fourth stage is comparable to a combination of the stages 4 and 5 from the Schmeling classification [65].