Table 5. Results of factorial analysis for thyroid endpoints of OVX rat treated with PTU, PCBs, and AP.

Variance source		Serum tT3		Serum tT4		Thyroid/body weight ratio		Follicular epithelium/colloid ratio
		F	P	F	P	F	P	F	P
Main effect	PTU	44.93	<0.001a	54.30	<0.001a	65.21	<0.001a	23.59	<0.001a
	PCBs	0.15	0.70	67.71	<0.001a	13.17	<0.001a	0.28	0.60
	AP	31.76	<0.001a	26.82	<0.001a	72.82	<0.001a	81.94	<0.001a
Interaction	PTU*PCBs	12.99	0.001b	1.12	0.295	0.38	0.54	7.45	0.008b
	PTU*AP	0.14	0.71	0.33	0.57	2.12	0.15	7.62	0.007b
	PCBs*AP	12.95	0.001b	2.56	0.11	1.33	0.25	1.21	0.27
	PTU*PCBs*AP	44.52	<0.001b	8.50	0.005	2.48	0.12	26.46	<0.001b