Table 2 Summary of the study population characteristics

Age – Years: mean (95 % confidence interval)

11.3 (11.2, 11.5)

11.5 (11.3, 11.6)

Age Range

10–14 years

10–12 years

Age group 1 (10,11): frequency (proportion)

n = 179 (61 %)

n = 46 (49 %)

Age group 2 (12,13,14): frequency (proportion)

n = 113 (39 %)

n = 47 (51 %)

Sex: frequency (proportion)

M = 272 (93 %)

M =90 (97 %)

F = 20 (7 %)

F = 3 (3 %)

Weight (kg): mean (95 % confidence interval)

M = 43.1 (41.9, 44.3)

M = 43.4 (41.4, 45.4)

F = 44.1 (40.4, 47.8)

F = 35.8 (27.6, 44.1)

Height (cm): mean (95 % confidence interval)

M = 151.2 (150.2, 152.2)

M = 151.4 (149.8, 153.0)

F =151.3 (146.7, 155.9)

F = 145.5 (133.3, 157.6)

Dominant Hand (proportion)

R = 258 (88 %)

R = 81 (87 %)

Hand: frequency (proportion)

L = 34 (12 %)

L = 12 (13 %)