Table 4: List of contributing strata and OR metrics satisfying the meta-analysis criteria. Results of the Chi-square test for homogeneity ( 𝑃 values and degrees of freedom, DOF) are shown for each meta-analyzed congener. Note that congener 118 is statistically heterogeneous ( 𝑃 < 0 . 0 2 5 ). However, removal of the weighted outlier [46] indicated homogeneity in the remaining strata. A combined test of all congeners indicated overall homogeneity ( 𝑃 > 0 . 1 0 and 37 DOF).

Study (strata)Percentile typePCB congenerORLCLUCLHomogeneity test (Chi-Square DOF)

Spinelli et al., 2007 [42]Tertile280.950.671.34 𝑃 > 0 . 1 0 (1)
Cocco et al., 2008 [46]Quartile281.600.803.20

Spinelli et al., 2007 [42]Quartile991.270.861.87 𝑃 > 0 . 1 0 (1)
De Roos et al., 2005 [26]Quartile990.770.282.10

Engel et al., 2007-J [41]Quartile1181.700.903.50 𝑃 < 0 . 0 2 5 (6)
Engel et al., 2007-C [41]Quartile1185.401.7017.10
Spinelli et al., 2007 [42]Quartile1181.771.152.72
De Roos et al., 2005 [26]Quartile1180.730.291.84
Cocco et al., 2008 [46]Quartile1180.400.200.80
Laden et al., 2010 [48]Quartile1180.810.421.56
Bertrand et al., 2010 [47]Quintile1181.400.762.50

Engel et al., 2007-J [41]Quartile1381.700.803.20 𝑃 > 0 . 1 0 (5)
Engel et al., 2007-C [41]Quartile1384.401.5012.60
Spinelli et al., 2007 [42]Quartile1381.460.982.18
Cocco et al., 2008 [46]Quartile1381.100.602.00
Laden et al., 2010 [48]Quartile1380.950.491.83
Bertrand et al., 2010 [47]Quintile1381.800.983.20

Engel et al., 2007-J [41]Quartile1532.001.003.90 𝑃 > 0 . 1 0 (6)
Engel et al., 2007-C [41]Quartile1532.200.905.20
Spinelli et al., 2007 [42]Quartile1531.791.172.72
De Roos et al., 2005 [26]Quartile1531.590.634.00
Cocco et al., 2008 [46]Quartile1531.000.702.50
Laden et al., 2010 [48]Quartile1530.820.431.56
Bertrand et al., 2010 [47]Quintile1532.101.103.80

Spinelli et al., 2007 [42]Quartile1561.771.142.74 𝑃 > 0 . 1 0 (1)
De Roos et al., 2005 [26]Quartile1562.700.977.50

Spinelli et al., 2007 [42]Quartile1701.801.162.79 𝑃 > 0 . 1 0 (2)
De Roos et al., 2005 [26]Quartile1701.730.734.14
Cocco et al., 2008 [46]Quartile1701.000.501.80

Spinelli et al., 2007 [42]Quartile1801.911.193.07 𝑃 > 0 . 1 0 (4)
De Roos et al., 2005 [26]Quartile1803.501.349.15
Laden et al., 2010 [48]Quartile1801.030.522.02
Cocco et al., 2008 [46]Quartile1801.500.703.20
Bertrand et al., 2010 [47]Quintile1802.401.304.50

Spinelli et al., 2007 [42]Tertile1831.220.871.71 𝑃 > 0 . 1 0 (1)
De Roos et al., 2005 [26]Quartile1831.020.362.93

Spinelli et al., 2007 [42]Quartile1871.921.232.98 𝑃 > 0 . 1 0 (1)
De Roos et al., 2005 [26]Quartile1871.220.493.08