Less than 20% of insured adults consider themselves knowledgeable about their health benefit plans, according to a new survey.

The lack of knowledge comes as open enrollment for most health care plans is about to begin. Between October and December, employers have open enrollment periods, typically the only chance for millions of Americans workers to make changes to their health benefits plans for the coming year.

“Making health benefits choices during open enrollment can be confusing, especially as people cope with the current economic situation,” said Wendy Richards, national medical director for Aetna, in a statement. “However, consumers who do a little homework up front are in a better position to choose a plan that will help them stay fit and healthy, manage any chronic health conditions that may impact their family, and even save money in the long run.”

“People should arguably be spending more time reviewing their options at Open Enrollment this year in light of the uncertain economy,” said Tracey Baker, a certified financial planner and former chair of the Financial Planning Association’s National Capital Area. “Open enrollment is a fantastic opportunity for consumers to evaluate their health benefits plan and make choices that are best for their health and wallet. They need to take advantage of it.”

The survey found that more insured women ages 24-44 (the main household decision makers) say they are spending less time researching available plans this year than they reported five years ago. The survey was prepared for Plan for Your Health, a partnership of national health insurer Aetna and the Financial Planning Association.

Five years ago, 30% of respondents spent less than one hour reviewing the available plans before settling on one. This year, about half the women report taking this approach.

To help consumers understand their health benefits better, Richards and Baker co-authored Navigating Your Health Benefits for Dummies, a free, 64-page consumer guide with hints and other information about health benefits. The update to the 2006 edition is available at www.PlanforYourHealth.com.