instruction:
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.
question:
Question: Does bone mineral density vary as a function of the rate of joint space narrowing in the hip?
Answer: Patients with a rapid rate of JSN of the asymptomatic hip after unilateral THR are characterized by elevated local and remote BMD. The local elevation in BMD implies that increased local bone density may contribute to or serve as a marker for increased risk of development of OA (assuming that JSN can be used as a predictive marker). The presence of elevated BMD in the spine suggests that there are systemic as well as local aspects of OA pathogenesis, at least in patients with one THR and rapid JSN in the contralateral hip.
answer:
yes


question:
Question: Is allogeneic red blood cell transfusion an independent risk factor for the development of postoperative bacterial infection?
Answer: These data support the hypothesis that allogeneic red cell transfusion is an independent risk factor for the development of postoperative bacterial infection in patients undergoing colorectal surgery. This association provides further reason to minimise exposure to allogeneic transfusions in the perioperative setting.
answer:
yes


question:
Question: Is self-reported body fat change in HIV-infected men a marker of decline in physical health-related quality of life with aging , independent of co-morbidity?
Answer: Negative self-perceived body fat changes were associated with decline in physical health related quality of life, independent of comorbidities, and may be a marker of an increased risk for physical function decline with aging.
answer:

yes