Definition: Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.
Input: Question: Is hER-2 expression prognostic in osteosarcoma ; a Children 's Oncology Group prospective biology study?
Answer: HER-2 expression is not prognostic in osteosarcoma in the context of this large prospective study. HER-2 expression cannot be used as a basis for stratification of therapy. Identification of potential prognostic factors should occur in the context of large multi-institutional biology studies.
Output:
no