According to a recent report issued by the nonprofit National Committee for Quality Assurance, and based on performance results from 563 managed-care plans, America’s health-care system is plagued by enormous quality gaps. Among the findings of the NCQA’s 2004 State of Health Care Quality: If Americans with hypertension received care through one of the country’s top 10 percent of health plans (which control blood pressure in about 71 percent of such patients), up to 26,000 deaths could be prevented annually.

Obviously, your choice of a managed-care plan can have a big effect on the quality of medical treatment you receive. If you are one of the 65 percent of U.S. workers who can choose among plans, you should start your selection by weighing the fundamental differences between the two basic types: HMOs and PPOs.

HMOs, or health maintenance organizations, currently enroll about 25 percent of consumers. These plans typically charge lower premiums, and require fewer out-of-pocket expenses, than preferred provider organizations (PPOs), which account for about 55 percent of all covered workers. The tradeoff is that HMOs are generally more restrictive than PPOs in the health-care providers you can use. While the average family premium paid in 2004 was about the same for HMOs ($2,674) and PPOs ($2,691) – according to data from the Kaiser Family Foundation’s 2004 Employer Health Benefits survey – the average family deductible for an HMO was just $80, compared with an average deductible of $287 for a single person enrolled in a PPO. And that’s for someone who stays within his PPO’s network of providers. Go outside the network, cost data show, and the deductible nearly doubles.

Thus, an HMO is likely best for people who need to keep out-of-pocket expenses low and can be flexible about the providers they use. PPOs, meanwhile, should appeal to consumers who want the ability to choose any doctor. When we surveyed some 36,000 Consumer Reports subscribers last year about their experiences with managed-care plans, HMOs scored slightly higher in overall satisfaction than PPOs, although people in HMOs had more trouble obtaining care than members of PPOs. At the same time, nearly one-third of all PPO members reported billing problems with their plans – about three times the rate for people in HMOs.

When deciding among managed-care plans offered by your employer, ask to see the plans’ lists of participating physicians. Are your current doctors among them? If you want to use new doctors, call them to verify that they are still providers under the plan and are willing to take on new patients. Also, note whether the plans will pay for alternative-medicine treatments. Most PPOs and HMOs cover chiropractic visits, we’ve found, but only about half cover acupuncture.

We recently rated 35 HMOs and 41 PPOs, based on our survey of subscribers. (The ratings, presented in the September issue of Consumer Reports magazine, also are available to our online subscribers at www.ConsumerReports.org.) In addition to receiving an overall satisfaction score, each plan was rated on such measures as access to doctors and care, choice of doctors and customer support and billing.

Information about managed-care plans also is available, for free, at the NCQA Web site, www.healthchoices.org. The group, which is partly funded by the health-care industry, provides report cards on 216 HMOs and 20 PPOs. While the NCQA rates plans on a number of areas – including access to doctors, chronic-care treatment and customer service – the organization’s data collection requires the voluntary cooperation of the health plans themselves.

Finally, you can check on complaints against a plan by calling your state department of insurance. For contact information, visit the National Association of Insurance Commissioners at www.naic.org/state_contacts/sid_websites.htm.