Table 2.
Average annual percent change in serum concentrations and 95% confidence interval among subgroups of each categorical covariate
| Subgroups | Average annual percent change with 95% confidence interval | |||||
|---|---|---|---|---|---|---|
| PFOA | PFOS | PFHxS | PFNA | PFDA | ||
| Race/Ethnicity | white | −11.4* (−14.1, −8.7) | −10.5* (−13.4, −7.5) | −8.6* (−11.9, −5.2) | 1.2 (−3.5, 6.1) | 2.0 (−2.8, 7.1) |
| Hispanic | −11.9 (−16.6, −6.9) | −14.2* (−18.8, −9.3) | −9.8* (−14.9, −4.3) | −6.5 (−14.5, 2.1) | −1.7 (−10.5, 8.0) | |
| Othersa | −7.7* (−13.0, −2.2) | −9.3* (−14.6, −3.7) | −3.3 (−10.0, 4.0) | 2.4 (−6.1, 11.5) | 0.6 (−8.5, 10.5) | |
| Education | Less than college | −12.4* (−15.4, −9.4) | −11.4* (−14.5, −8.2) | −7.7* (−11.3, −4.0) | −3.2 (−8.4, 2.2) | 0.7 (−4.8, 6.5) |
| Bachelor | −9.2* (−12.9, −5.4) | −9.9* (−13.6, −5.9) | −6.3* (−10.6, −1.7) | 2.4 (−3.2, 8.2) | 2.0 (−4.6, 9.0) | |
| Graduate or professional | −10.8* (−15.9, −5.3) | −12.9* (−18.8, −6.7) | −12.8* (−19.7, −5.2) | 1.9 (−8.6, 13.6) | −2.7 (−11.5, 7.0) | |
| Homeownership | No | −9.2* (−12.9, −5.3) | −10.1* (−13.7, −6.4) | −4.3 (−9.0, 0.7) | −3.7 (−9.7, 2.5) | 1.6 (−5.1, 8.7) |
| Yes | −11.6* (−14.1, −9.1) | −11.3* (−14.0, −8.4) | −9.8* (−12.7, −6.8) | 1.3 (−3.2, 6.0) | 0.1 (−4.5, 4.9) | |
For PFOA, PFOS, and PFHxS, we provided significance (* or **) of p-value of the null hypothesis that the regression coefficient (β) of ‘year’ equals to zero.
For PFNA and PFDA, we provided significance (*) of p-value of the null hypothesis that the regression coefficient (β) of ‘year2’ equals to zero.
*
p-value < 0.05
a
Includes 28% black, 48% Asian, and 28% multiracial.