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.

Ex Input:
Question: Is assessment of joint space narrowing with conventional standing antero-posterior radiographs : relief in mild-to-moderate pain a confounder in recent osteoarthritis structure-modifying drug trials?
Answer: Knee pain relief did not bias the report of a structure-modifying effect of glucosamine sulfate in two recent long-term trials, possibly due to the mild-to-moderate patient characteristics. Consensus deliverables should acknowledge that the potential limitations of conventional standing antero-posterior radiographs should not be overestimated since they may not apply to all patient populations and to all studies using this gold standard technique.

Ex Output:
no

Ex Input:
Question: Do extremely cold and hot temperatures increase the risk of diabetes mortality in metropolitan areas of two Chinese cities?
Answer: The results indicate that both extremely cold and hot temperatures increase diabetes mortality in different manners in Harbin and Chongqing. Diabetes education programs should include information on either managing or combating the effects of extreme hot and cold weather.

Ex Output:
yes

Ex Input:
Question: Do the periurethral glands significantly influence the serum prostate specific antigen concentration?
Answer: The greatest difference in median PSA levels that could be found between men with and without periurethral glands when using 3 different ultra-sensitive assays was 0.01 ng./ml., indicating that the periurethral glands do not have a clinically significant effect on serum PSA concentration after radical prostatectomy. Thus, a serum PSA level above the residual cancer detection limit following radical prostatectomy, even if obtained with a ultra-sensitive assay, reflects either malignant or benign residual prostatic tissue, rather than the presence of periurethral glands.

Ex Output:
no