Table 4.

Skeletal maturity indices with mean age, age range, and frequency for each individual grade

Girls (n = 1296 assessments from nine raters and with two assessments per rater)
Olecranon	Mean age (years)	Range	%	Radius	Mean age (years)	Range	%	Ulna	Mean age (years)	Range	%	Digital	Mean age (years)	Range	%
1	10.5	1.4	4.8	R3*	11.3	0.0	0.1	U3	10.1	0.5	0.2	SS1	10.2	1.1	2.2
1.5	11.1	0.3	0.3	R4	10.9	1.4	0.8	U4	10.8	3.4	5.4	SS2	11.3	4.4	7.6
2	11.2	2.3	5.3	R5	10.9	3.2	3.9	U5	11.7	4.5	14.4	SS3	11.8	4.0	12.7
2.5	11.1	1.9	0.3	R6	11.7	4.6	14.0	U6	12.4	4.3	18.4	SS4	12.5	5.4	17.1
3	11.4	3.1	7.2	R7	12.2	4.6	14.7	U7	13.1	6.8	24.3	SS5	12.8	5.8	7.4
3.5	11.6	2.3	0.5	R8	12.8	6.6	22.8	U8	13.8	6.6	21.8	SS6	13.0	6.6	20.3
4	12.2	5.2	22.2	R9	13.7	6.6	21.8	U9	14.9	4.6	15.6	SS7	14.2	6.0	22.8
4.5	12.4	3.2	2.4	R10	14.4	6.8	14.3					SS8	15.1	4.6	10.0
5	14.1	5.6	56.9	R11	15.2	4.3	7.6
Boys (n = 756 assessments from nine raters and with two assessments per rater)
Olecranon	Mean age (years)	Range	%	Radius	Mean age (years)	Range	%	Ulna	Mean age (years)	Range	%	Digital	Mean age (years)	Range	%
1	13.0	3.5	11.0	R4*	13.3	0.0	0.1	U3	11.8	0.0	0.2	SS1	12.6	2.9	5.2
1.5	13.3	0.0	1.2	R5	12.8	4.4	6.7	U4	12.6	4.4	7.4	SS2	13.2	4.9	0.1
2	13.5	4.2	10.8	R6	13.4	5.2	18.7	U5	13.7	5.2	20.4	SS3	14.2	4.6	13.6
2.5	12.7	2.9	0.4	R7	14.2	5.2	15.2	U6	14.3	5.2	24.5	SS4	14.1	5.0	19.6
3	13.5	4.4	8.4	R8	14.6	3.0	23.0	U7	14.7	3.0	21.0	SS5	14.6	2.6	12.6
3.5	14.2	0.0	1.1	R9	15.5	3.5	17.3	U8	15.3	4.2	16.3	SS6	14.7	4.6	6.9
4	14.4	5.0	24.2	R10	15.4	3.8	11.8	U9	16.0	3.1	10.2	SS7	15.5	3.3	14.4
4.5	14.7	1.8	3.3	R11	16.3	2.6	7.1					SS8	16.1	2.8	17.3
5	15.6	4.2	39.6

%, frequency.

^aTo be interpreted with caution as n = 1 for that particular grade/mean age.