25616
A total of 342 children ( 111 males and 231 females ) who were negative for antithyroid antibodies ( TgAb , TPOAb ) and were found to have no abnormalities on ultrasonographic examination of the thyroid gland were divided into 6 age groups : 4 - 6 years ( 45 children ) , 7 - 8 years ( 40 ) , 9 - 10 years ( 53 ) , 11 - 12 years ( 65 ) , 13 - 14 years ( 83 ) , and 15 years ( 56 ) for the study .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None