Table 4 The effect of tumor size (mm) on the presence individual postoperative risk factors. After adjustment for multiple testing using the Bonferroni method, p values < 0,008 are considered statistically significant

Contralateral tumor

0.994

0.970–1.019

0.653

Aggressive histology

1.014

0.987–1.042

0.307

Extrathyroidal extension

1.019

0.996–1.042

0.115

Positive surgical margins

1.030

0.007–1.052

0.009

Lymph node metastasis

1.001

0.982–1.021

0.893

Vascular invasion

1.047

1.023–1.071

0.000087