As Boomers start to retire, they're confused about whether or not they want annuities—and the confusion stems not from old age but from a fear of losing control, according to results of studies from BlackRock and Harvard University released last week at a press briefing in New York.

Retirement income is a growing concern nationwide, but because retirees themselves don't really know whether they do or don't want a guaranteed income stream, employee 401(k) plan sponsors may become more responsible for helping people make that choice, the studies conclude.

"I don't think the U.S. public knows what it wants," said David Laibson, a Harvard College professor and aging expert with the National Bureau of Economic Research whose research focuses on behavioral economics and human irrationality. "You don't get a radically different answer when you change the wording of a question about whether you want chocolate or vanilla ice cream, but with annuities you do."