Table 1.

Baseline characteristics of the 1,221 women with metals measured from toenails, The Sister Study

	N	%
Race/Ethnicity
Non-Hispanic white	1,104	90
All other race/ethnic groups	117	10
Highest level of education
Less than high school, High school graduate or equivalent	130	11
Some college	382	31
College degree or higher	709	58
Cigarette smoking status
Never	815	67
Past	315	26
Current	91	8
Menopause status at baseline
Premenopausal	865	70.8
Postmenopausal	356	29.2
Year of toenail collectiona
2003	5	0
2004	16	1
2005	76	6
2006	192	16
2007	504	42
2008	317	26
2009	100	8
	Mean	SD
Age at baseline (years)	47.0	6.1
Hours per week of physical activity	2.7	2.8
Examiner measured baseline BMI	26.7	6.1
Self-reported baseline BMIa	26.4	5.7
Self-reported follow-up BMI	27.1	6.2
Pack-years of smokinga,b	10.7	11.3

^aYear of toenail collection missing for 9 women; self-reported baseline BMI missing for 4 women; pack-years of smoking missing for 3 women

^bAmong current or past smokers