Table 4.

Effects of thyroid dose and tumor size on lymphovascular invasion.

	OR (95% CI)	p-value	AIC a		OR (95% CI)	p-value	AIC
POC or its components				Tumor size
Non-adjusted				Non-adjusted
POC	1.009 (1.000-1.017)	0.041	522.337	Tumor size, mm	1.202 (1.064-1.358)	0.003	517.436
Sex	1.535 (0.941-2.506)	0.086	523.567
Age at exposure, years	0.994 (0.955-1.034)	0.754	526.323
Latency period, years	0.971 (0.935-1.009)	0.139	524.262
Age at operation, years	0.983 (0.957-1.010)	0.213	524.886
Thyroid dose, mGy (log)	1.270 (1.055-1.530)	0.012	519.968
	Model 1A		521.468		Model 1B		519.473
Sex	1.393 (0.843-2.301)	0.196		Sex	1.481 (0.899-2.440)	0.196
Age at exposure, years	1.033 (0.982-1.086)	0.207		Age at exposure, years	0.990 (0.951-1.031)	0.636
Latency period, years	0.983 (0.945-1.022)	0.395		Latency period, years	0.980 (0.943-1.020)	0.326
Thyroid dose, mGy (log)	1.354 (1.061-1.728)	0.015		Tumor size, mm	1.198 (1.058-1.355)	0.004
	Model 2A		521.884		Model 2B		517.589
Sex	1.449 (0.881-2.383)	0.144		Sex	1.449 (0.881-2.383)	0.144
Age at operation, years	1.002 (0.971-1.034)	0.912		Age at operation, years	1.002 (0.971-1.034)	0.912
Thyroid dose, mGy (log)	1.260 (1.013-1.568)	0.038		Tumor size, mm	1.201 (1.063-1.358)	0.003
Models combining POC components and tumor size
	Model 3A		515.101		Model 3B		514.593
Sex	1.395 (0.840-2.315)	0.198		Sex	1.439 (0.870-2.380)	0.157
Age at exposure, years	1.029 (0.977-1.083)	0.277		Age at operation, years	1.004 (0.972-1.037)	0.819
Latency period, years	0.989 (0.950-1.029)	0.588		Thyroid dose, mGy (log)	1.285 (1.026-1.610)	0.029
Thyroid dose, mGy (log)	1.365 (1.063-1.752)	0.015		Tumor size, mm	1.209 (1.069-1.369)	0.003
Tumor size, mm	1.200 (1.059-1.359)	0.004

^aAkaike information criterion.

Numbers in bold indicate statistical significance.