Table 3.

Correlation of IRT Level and CF Risk in Newborns with One Mutant Allele Detected Using the ACMG CFTR 23 Mutation Panel

IRT level (ng/mL)	IRT percentile	No. CF/No. infants	CF risk, % (binomial exact 95% CI)	Relative risk, (95% CI) compare with IRT<99	P-value compare with IRT<99
<99	96.0–98.9th	13/1029	1.3 (0.7, 2.2)
100–124	99.0–99.3th	9/147	6.1 (2.8, 11.3)	4.8 (2.1, 11.1)	<0.0001
125–149	99.4–99.7th	8/48	16.7 (7.5, 30.2)	13.2 (5.7, 30.3)	<0.0001
≥150	99.8–100th	15/31	48.4 (30.2, 66.9)	38.3 (20.0, 73.4)	<0.0001