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.
Q: Question: Is concomitant lamotrigine use associated with decreased efficacy of the ketogenic diet in childhood refractory epilepsy?
Answer: Lamotrigine treatment during KD is associated with a decreased efficacy of the KD.
A:
yes