Table 2. Prevalence of Thyroid Pyramidal Lobes on US and CT in Six Institutions.

Investigators	US	CT
A (n = 100)	59	59
B (n = 100)	45	57
C (n = 100)	44	45
D (n = 100)	37	58
E (n = 100)	27	29
F (n = 82)	18	28
Mean ± SD	38.3 ± 14.5	46 ± 14.5

Note.- Significant difference in prevalence of thyroid pyramidal lobe between institutions was found (p < 0.001). CT = computed tomography, US = ultrasonography