Table 3.

Associations between carbon monoxide level in ambient air and lung function

	CO	Mean±Standard deviation	P value
FEV1(percent predicted1)	0-9ppm	91±17	0.70
	>9ppm	89±15
FVC(percent predicted1)	0-9ppm	92±13	0.66
	>9ppm	90±15
PEF(percent predicted1)	0-9ppm	101±27	0.02
	>9ppm	89±18

¹NHANES predicted values for African Americans