Granola Boy good idea for a poll but I think the question is too subjective. Often is a subjective term and different people will interpret it differently. I would break it down into time period so their is no room for interpretation. ie. do you get checked every 4 months, 6 months, once per year, every 2nd year, never, etc. Just a suggestion though.
To answer your question though I see my doctor about 3-4 times per year, but I usually only get a complete physical once per year, ie blood, urine tests, etc. I don't know if this would be considered often.