Clinical Characteristics
PTC
With a mean age of 14.60 ± 3.52 years and a male-to-female ratio of 27:55, a total of 164 PTC patients were enrolled. A total of 103 children were pathologically identified as ETE, while 61 children were pathologically identified as non-ETE. Using stratified sampling, all patients were randomly assigned to a training group (n = 115) and a validation group (n = 49). The clinical data and sonographic characteristics of the training and validation groups are displayed in Table 