Frustrated with your Medicare coverage? You have until Dec. 7 to look for new options.

That's the last day of open enrollment for current beneficiaries. Changes made to your plan go into effect Jan. 1.

With speculation still swirling about possible changes to the program's "hold harmless" provision — a rule that will stick people who are delaying Social Security and higher income beneficiaries with big premium hikes for 2016 — managing costs and benefits is more important than ever, experts said.

"It really takes an individualized assessment to find the right plan," said Casey Schwarz, senior counsel for education and federal policy at the Medicare Rights Center. "The one that's right for your neighbor or even your spouse might not be the one for you."

That's certainly true for couples with different health profiles, where one very healthy spouse might choose a plan that's low on premiums and higher on out-of-pocket costs, while the sicker spouse chooses a higher premium and lower out-of-pocket costs.

But it could also be true for couples in more comparable health situations, she said.

"I was speaking with someone the other day who uses a brand-name medication, and his wife takes a different one. There wasn't a single plan in the lowest cost tier that had them both, so they chose separate plans," she said.

Managing two plans in one household could be a hassle but potentially worth it if it means savings of hundreds or thousands of dollars a year.

Here are some other tips to keep in mind as you choose.

Look to the stars. Check out Medicare.gov for access to the health plans available to you. Plans carry a star rating of one to five, with five being the best. The plans earn stars based on measures such as customer service, how many of their participants have well-managed blood sugar levels, how many got their flu shot, and the like. Schwarz said these measures are best used to help distinguish between two or more finalists you've already narrowed down according to coverage and cost.

Study up. Make sure you understand fully the final plans you are considering. One reader of this column shared some frustrating experiences as he transitioned from COBRA to Medicare this year. While the move ultimately meant his total costs were cut in about half, he spent many hours on the phone with his insurance provider, haggling over getting access to the right dosage of a prescribed medication.

In theory, doctors can write prescriptions for whatever amount of medication they feel is suitable for a patient, but insurers increasingly are scrutinizing those orders.

Watch your step. Some drug plans offer cost incentives for step therapy, the practice of starting a patient on the lowest-cost drug and moving to higher-cost alternatives if the first one doesn't work. Patients may view these rules as very heavy handed.

Wanderlust? If you spend part of the year in another state, make sure your plan can travel with you, experts said. Some plans, for example, only cover you in your home base.

The bottom line, experts said: Don't leap for a low-premium plan just to save a few dollars of monthly cost. Look for a plan's total out of pocket costs and deductibles, and find out about restrictions on drug dosing.

Janet Kidd Stewart writes for the Chicago Tribune.