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.

Example Input: Question: Is previous laparotomy a contraindication to laparoscopy-assisted gastrectomy for early gastric cancer?
Answer: There was no difference in outcome following LAG between the PSURG and NSURG groups in the present study. The PSURG patient is not contraindicated for LAG assuming careful attention is given for all operative procedures, including port insertion and dissection of intra-abdominal adhesions.
Example Output: no

Example Input: Question: Is central venous saturation an alternative to mixed venous saturation during cardiopulmonary bypass in coronary artery surgery patients?
Answer: Although mean biases between the measurements were low, limits of agreement were too large to provide a clinically acceptable estimation of SvO(2) by ScvO(2) in these conditions. Variations in regional oxygen consumption seem to be the main factor worsening the relationship.
Example Output: no

Example Input: Question: Does adherence to migraine treatment depend on the number of prescribed medications?
Answer: There is no difference in adherence to monotherapy or politherapy (one to four drugs) for the prophylaxis of migraine.
Example Output:
no