Choosing the right HMO requires careful examination of many factors

From CNN Medical Correspondent Elizabeth Cohen

ATLANTA (CNN) -- All HMOs look good in ads that feature caring doctors and satisfied patients.

So how do you know which HMO is best? It's hard. There's not a lot of objective information out there for consumers.

"It's like going to a supermarket and buying food where there's no nutritional labeling, no price on it, no unit pricing on the food, so you'd be shopping blind," said New York City Public Advocate Mark Green.

The health policy editor of Consumer Reports Magazine said to ask a lot of people a lot of questions.

"You might ask the doctors whether they're happy with the HMO, and whether or not they have to go through a lot of hoops to get you care," said Trudy Lieberman. "Because if the HMO is controlling services very tightly, then maybe that's not the plan for you."

Ask your benefits administrator if employees complain more about one HMO than another.

Consumer Reports also said make sure the plan has a reasonable selection of specialists.

"If you need a podiatrist and the plan has only two, and they're very far away from you, them maybe that's not the plan you want to go to," Lieberman said.

And once you've chose a doctor, that's not the end.

Your doctor might recommend a procedure or drug and the HMO can still say they won't pay for it. So if you will need certain tests or prescriptions, ask the HMO if they're covered.

Once you have chosen your HMO, be prepared to be your own advocate. You may end up fighting for the coverage you paid for.