MM: Letting them buy in at an earlier age would smooth their transition to Medicare. Because Medicare has to take all comers, people would no longer have to worry about preexisting conditions and being rejected by insurers in the individual market at an age when health conditions start to surface. But that creates other challenges. If all the healthy people continue to buy insurance from private plans and only turn to Medicare when they get sick, the costs to Medicare would be very high. This unlevel playing field would lead policy makers to tough choices: Should Medicare be subsidized to keep costs low? If so, who should pay for that? That could mean higher payroll taxes which many people believe are necessary. Others are vehemently opposed to higher taxes.

TL: How serious is Medicare’s so-called waste, fraud, and abuse problem?

MM: We know that there is fraud on the part of doctors and hospitals that game the system, and that should be aggressively handled. The issues of waste and abuse are more subtle. Was a particular treatment or test necessary, or was it wasted money? Sometimes we can judge that only after the fact. One person’s waste is another’s valued benefit. We need to know much more about what works and what doesn’t. This will require investment in research and communication, and it will take time to change the system. The public also needs to realize that refusing to insure certain tests and treatments that do not work is a good approach, not a bad one as some critics have charged.

Trudy Lieberman is a fellow at the Center for Advancing Health and a longtime contributing editor to the Columbia Journalism Review. She is the lead writer for The Second Opinion, CJR’s healthcare desk, which is part of our United States Project on the coverage of politics and policy. Follow her on Twitter @Trudy_Lieberman.