Table 7. Comparisons of interobserver variability.

Kappa value	Ultrasound examinations	Fine-needle aspiration cytology	Ultrasound elastography	Histopathological examination of the surgical specimen
Observers	4	2	4	2
k	0.6	0.77	0.79	0.83

Pathologist with a minimum experience of 3 years performed biopsies and histopathological examination. Ultrasound technologists with a minimum experience of 5 years conducted ultrasound examinations.

k-value: 0.1-0.2, slight agreement; 0.21-0.4, fair agreement; 0.41-0.6, moderate agreement; 0.61-0.8, substantial agreement; and 0.8-1, perfect agreement.