The fact that the standard pediatric hepatitis B vaccination series consists of three doses is a matter of common medical knowledge and routine public health observation, requiring no formal citation.
The claim states a standard medical fact regarding the administration of the hepatitis B vaccination series in children (typically given as a three-dose series at birth, 1-2 months, and 6-18 months, or within combination vaccines). Under Step 0, statements that are trivially true by definition or direct everyday observation/standard medical practice are classified as COMMON_KNOWLEDGE. Therefore, no citation is needed and the index lists are left empty.