For those 65 years and older on Medicare, the critically important open enrollment season runs from Oct. 15 to Dec. 7.

Open enrollment allows participants to change plans if they'd like. You can shift from a traditional Medicare plan to Medicare Advantage, change to a plan with a Medicare Part D prescription drug plan that better meets your needs, or make other changes.

Surprisingly few people take advantage of the option, but researching your choices is well worth the time and effort. For one thing, your health circumstances may change with time and a different plan might better meet your needs. For another, providers often adjust the terms of their plans.

The federal government's Medicare website offers a number of online tools, including the Medicare Plan Finder. The Plan Finder is designed to help comparison shopping.

That said, there are several good resources for additional guidance and comparison shopping. A few weeks ago, I was on Rural Money Matters by AARP on RFD TV. A number of the questions from viewers involved Medicare. The two experts from AARP recommended questioners take advantage of the State Health Insurance Assistance Program, or SHIP, offered in every state. (SHIP is the Minnesota Senior LinkAge Line.) You can get free one-on-one assistance reviewing your current health and prescription drug plan options with SHIP.

The Medicare Rights Center offers a free national helpline to answer questions about benefits, enrollment decisions and many other issues. The organization offers clear and understandable guides to your Medicare choices.

Another resource is the book "Get What's Yours for Medicare," by journalist Philip Moeller. He probably knows more about Medicare than any other journalist I know, and he goes into detail about the program from the consumers' perspective. Also, after fielding thousands of questions since the book came out — along with a co-authored book on Social Security from the recipient's perspective — he has posted an updated "most frequently asked" section at his curated "Get What's Yours" online archive.

There are a number of important changes coming to Medicare. Among the most critical ones: Medicare will negotiate some drug prices (starting in 2026), limits to Medicare Part D premium increases (starting in 2024), and out-of-pocket drug costs on Part D capped at $2,000 per year (starting in 2025); and all vaccines free under Part D (starting in 2023). In the meantime, check out your current plan to see if you'd like to stay with it or change.