John McCain unveiled a health care reform plan yesterday focused on lowering health care costs and increasing consumer choice of plans.

His plan, described by the Arizona senator in a speech delivered in Des Moines, Iowa, yesterday, does not endeavor to provide insurance to all of the approximately 47 million Americans who are uninsured.

"I offer a genuinely conservative vision for health care reform, which preserves the most essential value of American lives - freedom," McCain said at the event, according to a copy of his speech provided by the campaign.

Like health care reform plans proposed by former Massachusetts governor Mitt Romney and former New York City mayor Rudy Giuliani, two of McCain's rivals for the Republican nomination for president, and one proposed by President Bush, McCain's plan is centered on tax refunds that allow people to buy insurance on the individual market. McCain's plan differs slightly from other Republican proposals; it would offer a tax credit, rather than a deduction.

Under the McCain proposal, laws that give employers a tax break when they purchase insurance for employees would be eliminated. Instead, the program would give everyone a flat tax credit of $2,500 for individuals or $5,000 for families to purchase health insurance wherever they choose.

Doug Holtz-Eakin, a senior policy adviser to McCain who helped develop the plan, said individual tax credits will give people more choices about what type of insurance to buy and will eliminate tax disparities that hurt people who can't get insurance through their employer.

The plan would encourage people to purchase coverage in groups to spread out risk. Instead of choosing simply between an employer-based plan and an individual plan, McCain's proposal envisions local and national groups that would offer other choices to their members.

"Some are already content with the choices and advice offered by their employer," McCain said. "Fine. But Americans should be able to choose who they trust. If a church or professional organization wishes to sponsor insurance for their members, they should be able to do so."

Several health care policy analysts said the plan could expand insurance choices for some people but has the potential to backfire by undermining employer-based coverage for many workers.

"If you're not careful, it could lead to a substantial decrease in the number of people with coverage," said Stuart Altman, the dean of the Heller Graduate School for Social Policy & Management at Brandeis University, who has frequently advised politicians on health care reform.

Individual health insurance plans are often more expensive - or include major exclusions - for sick and old customers, because they don't spread out risk like group plans.

"What we've found is that the individual market doesn't work very well," Altman said.

According to the nonpartisan Kaiser Family Foundation, an average family health insurance policy cost more than $11,000 last year. McCain indicated in his speech that states might develop means to help lower-income individuals buy insurance, but critics said $5,000 would not bring many uninsured families much closer to affording coverage.

"If you think about what an average premium is right now for employer-based coverage - it's about $12,000 per family - then a tax credit is obviously going to fall short," said Sara Collins, an assistant vice president at the Commonwealth Fund, a foundation that sponsors research on health care policy.

The health care plans that have been offered by Democratic candidates for president have been focused on providing universal health insurance coverage, but McCain said he believes health care costs are the main barrier for many who have been pushed outside the market. Rather than government plans and mandates, he said, the government can increase coverage by lowering the costs of care and encouraging competition.

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