The effects of the Korean reference value on the prevalence of osteoporosis and the prediction of fracture risk

Table 3 The mean bone mineral density (g/cm ² ) by age group

Age	Male KNHANES 2008–2011				Female KNHANES 2008–2011				NHANES III
Age	n	Mean	SD	T^*	n	Mean	SD	T^*	n	Mean	SD	T^*
20–29	976	0.9123	0.1336	a	1,236	0.7740	0.1045	a	409	0.8525	0.1189	a
30–39	1,569	0.8507	0.1195	b	2,098	0.7587	0.1030	b	518	0.8310	0.1210	a
40–49	1,591	0.8254	0.1160	c	2,071	0.7572	0.1043	b	444	0.7934	0.1273	b
50–59	1,449	0.7879	0.1118	d	1,996	0.6976	0.1011	c	450	0.7401	0.1196	c
60–69	1,412	0.7453	0.1125	e	1,778	0.6159	0.0881	d	454	0.6820	0.1206	d
70–79	962	0.6864	0.1103	f	1,283	0.5486	0.0876	e	556	0.6245	0.1088	e
80–89	183	0.6329	0.1176	g	306	0.3982	0.0809	f	420	0.5694	0.1057	f

SD, standard deviation; KNHANES, Korea National Health and Nutrition Examination Survey.
Welch test: p < 0.001.
^*Post-hoc analysis (Tamhane’s T2); the letters represent the significant difference by age group.

ISSN: 1471-2474