your income is weighed much more heavily than your paerents. And for grad health professions they require parental info anyway for most schools.
Are you working? If so then you might get a bigger refund if you file yourself. Assuming your parents don't object. And if they are forking over more than 50 percent of your living expenses or you live with them they are entitled to claim you. If not, they aren't entitled to but I wouldn't argue if they are paying your tuition.
Have you filled out your fafsa yet. If so, what is your EFC? Then find the schools cost of attendance. Minus out your efc and that should give you a good idea of your financial aid package. The amount you get is further reduced by any scholarships you receive.