Table 1.

Descriptive summary of study participants.

Variable	Mining (Frequency, %), N = 51	Control (Frequency, %), N = 50	P<*
Sex
Female	33 (64.7)	29 (58.0)	0.49
Male	18 (35.3)	21 (42.0)
Education category
< High school	7 (13.7)	4 (8.0)	0.0001
High school	30 (58.8)	10 (20.0)
Some college	10 (19.6)	13 (26.0)
College graduate	4 (7.8)	23 (46.0)
Married
Yes	30 (58.8)	24 (48.0)	0.28
No	21 (41.2)	26 (52.0)
Race
White	45 (88.2)	48 (96.0)	0.15
Other	6 (11.8)	2 (4.0)
Current smoker
Yes	14 (27.4)	11 (22.0)	0.53
No	37 (72.6)	39 (78.0)
Use coal for home heating
Yes	4 (7.8)	0 (0)	0.12**
No	47 (92.2)	50 (100)
Season
Summer	16 (31.4)	29 (58.0)	0.008
Non-summer (Spring/Fall)	35 (68.6)	21 (42.0)
	Mean (SD)	Mean (SD)
Age in years	53.8 (16.6)	44.6 (18.2)	0.009
Days wristband worn	6.88 (0.38)	7.20 (0.49)	0.0005
Hours spent outdoors	3.20 (3.37)	3.35 (3.20)	.81

^*P values based on chi-square tests for categorical variables and two-tailed t-tests for continuous variables.

^**Fisher’s exact test.