You will be given a definition of a task first, then some input of the task.
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: Does progression rates and sample size estimate for PPMS based on the CLIMB study population?
Answer: Our modern PPMS cohort is demographically similar to previously studied cohorts. PPMS is associated with faster disability accrual than ROMS. Current real-world observations of time to sustained progression will inform design of new clinical trials for PPMS.
Output:
yes