Table 3

Multiple regressions of the combined study group data

Response variable

Exposure variable

Homogeneity of slopes (p-value)

Common slope Estimate (SE) p-value

Common intercept (p-value)

Adjusted R- square

XER (N = 348)

CB-153

0.86

-0.01 (0.01), 0.34

0.05

0.029

p,p'- DDE

0.24

-0.03 (0.02), 0.12

0.005

0.034

XERcomp (N = 338)

CB-153

0.20

0.01 (0.02), 0.45

<0.001

0.087

p,p'- DDE

0.15

-0.006 (0.02), 0.71

<0.001

0.086

Response and exposure variables are ln-transformed in the analysis. Homogeneity of slopes: p-value for the test for homogeneity of slopes between study group and exposure variable. Common slope: the estimated common slope across study groups assuming no interaction. Common intercept: p-value for the test of a common intercept across study groups assuming a common slope. Adjusted R-square assuming a common slope.

Bonefeld-Jorgensen et al. Environmental Health: A Global Access Science Source 2006 5:12   doi:10.1186/1476-069X-5-12