Table 2 Effect modification of seminal calcium and Pb of sperm quality and nested model comparisons

Rapid progressive motility

 Estimate

− 10

− 0.021

− 0.2

1.2

− 0.096

 p value

0.056

0.99

0.68

0.029

0.87

 95% CI

− 20 to 0.28

-11 ~ 11

− 1.2 to 0.76

0.12 to − 2.2

− 1.2 to 1.1

 p value of nested model test

0.057

Slow progressive motility

 Estimate

− 2.4

− 1.9

− 0.27

0.28

0.26

 p value

0.32

0.49

0.23

0.24

0.32

 95% CI

− 7.1 to 2.4

− 7.16 to 3.42

− 0.70 to 0.16

− 0.18 to − 0.74

− 0.25 to 0.77

 p value of nested model test

0.41

Non-progressive motility

 Estimate

− 0.35

4

− 0.19

0.02

− 0.14

 p value

0.91

0.25

0.51

0.95

0.69

 95% CI

− 6.6 to 5.9

− 2.9 to 11

− 0.76 to 0.37

− 0.59 to − 0.63

− 0.81 to 0.54

 p value of nested model test

0.9

Sperm concentration

 Estimate

8.6

21

− 2.3

− 0.28

− 2

 p value

0.58

0.22

0.11

0.86

0.25

 95% CI

− 22 to 39

− 13 to 56

− 5.1 to 0.49

− 3.3 to − 2.7

− 5.3 to 1.4

 p value of nested model test

0.5

Sperm viability

 Estimate

− 9.3

2.5

− 0.37

1.1

− 0.021

 p value

0.29

0.83

0.63

0.18

0.99

 95% CI

− 27 to 8.2

− 20 to 25

− 1.9 to 1.1

− 0.55 to − 2.8

− 2.4 to 2.3

 p value of nested model test

0.38

Asthenozoospermia

 OR

6.2

0.27

1.1

0.83

1.1

 p value

0.05

0.22

0.2

0.055

0.34

 95% CI

− 22 to 39

− 13 to 56

− 5.1 to 0.49

− 3.3 to − 2.7

− 5.3 to 1.4

 p value of nested model test

0.03