Table 2 Calculation of specificity, sensitivity, PPV, NPV and accuracy in different scenarios

First scenario

Only the benign category in FNAC was categorised as benign (non-malignant), whereas atypical lesions, suspected of malignancy, and malignant categories were labelled as malignant

Second scenario

Benign and atypical categories were considered as non-malignant, but suspected of malignancy and malignant categories were considered malignant

Third scenario

Benign, atypical, and suspicious of malignancy categories were all classified as non-malignant, whereas only malignant category was classified as malignant