Of all the headaches that a conjured by Medicare physician reimbursement, the biggest source of problems according to readers are ever changing rules, according to just over 41 percent of respondents. Nearly 40 percent think that the rules are simply too complicated to be comprehensible. While others (17.6 percent) feel that system abuses (i.e. self-referrals that are not on the level) are what ruin the process for everyone.