. Author manuscript; available in PMC: 2014 Jun 1.

Published in final edited form as: Dev Psychol. 2012 Aug 13;49(6):1187–1193. doi: 10.1037/a0029424

Table 3.

Age at menarche (years) and difference scores^* by racial group and pubertal timing in 253 adolescent girls

	Racial Group¹		Pubertal Timing Group²
	White M (SD)	Non-White M (SD)	Early M (SD)	On-Time M (SD)	Late M (SD)
n	156	97	38	174	41
Age at Menarche First Report	12.63 (0.10)^a	12.05 (0.13)^b	10.54 (0.12)^a	12.39 (0.06)^b	14.18 (0.12)^c
In-person Interview Mean Age at Menarche	12.64 (0.10)^a	12.12 (0.12)^b	10.77 (0.12)^a	12.44 (0.06)^b	14.00 (0.12)^c
Phone Interview Mean Age at Menarche	12.41 (0.10)^a	11.86(0.13)^b	10.69 (0.16)^a	12.18 (0.08)^b	13.65 (0.16)^c
In-Person Interview Mean – Phone Interview Mean	0.52 (0.04)^a	0.52 (0.05)^a	0.63 (0.08)^a	0.51 (0.04)^a	0.44 (0.08)^a
Average difference (years): In-person & phone ^*	2.12 (0.18)^a	2.66 (0.23)^a	3.06 (0.35)^a	2.20 (0.17)^a	2.20 (0.35)^a
Average difference (years): In-person interview only^*	0.50 (0.06)^a	0.70 (0.08)^b	0.74 (0.12)^a	0.54 (0.06)^a	0.59 (0.12)^a
Average difference (years): Phone interview only^*	1.96 (0.18)^a	2.46 (0.23)^a	2.75 (0.36)^a	2.03 (0.17)^a	2.11 (0.35)^a

Note.

Difference scores represent discrepancy estimates calculated as the difference between the maximum reported age at menarche and minimum reported age at menarche across all assessments (in-person and phone), across in-person interviews only, and across phone interviews only.

Means are adjusted at sample mean of age = 15.1 years and SES = 37.43.

Means are adjusted at sample mean of age = 15.1 years. Means in same row not sharing superscripts (a, b, c) differ at p < .01 in the Bonferroni significant difference comparison. Comparisons between racial groups and pubertal timing groups were estimated separately. Annual clinic visits were conducted three times and phone visits were conducted quarterly at 3, 6, and 9 months (9 total) after each annual visit.