Instructions: 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: Are in patients with rheumatoid arthritis , Dickkopf-1 serum levels correlated with parathyroid hormone , bone erosions and bone mineral density?
Answer: In patients with RA, serum levels of DKK1 are significantly increased, correlate with PTH and are associated with increased risk of bone erosions and osteoporosis. However, this finding deserves confirmation in a larger and more selected population.
Output:
yes