The median net worth of families who purchase health insurance is nearly 35 times greater than the net worth of families who are uninsured, a government analysis found.

In contrast, the median income of families who purchased health insurance was $41,086-only 2.3 times greater than the median income of $17,690 for families who were uninsured.

Researchers at the US. Department of Health & Human Services’ Agency for Healthcare Research and Quality (AHRQ) say their study looked at the suggestion that because 23.8 million uninsured Americans under age 65 who do not have access to employer-based health insurance have incomes above the federal poverty line, they can afford to purchase policies if they so choose. The researchers say they found that the suggestion is untrue.

Measuring families’ median net worth-the value of their savings plus other assets minus debt rather than just income – provides more precise estimates of the percentage who could purchase policies if they chose to, the researchers said.

The researchers said prior studies used income alone to estimate how many more Americans could be covered by health insurance.

Carolyn M. Clancy

“This study has important implications for defining who can afford to pay for health insurance in the next wave of health care reform,” said AHRQ Director Carolyn M. Clancy in a statement. “We need accurate, evidence-based findings to ensure that we are providing policymakers with reliable information.”

Using national survey data, the researchers found that the median net worth of families who purchased health insurance was $105,819, compared to $3,057 for families who were uninsured. Median net worth means that half the families had net worth above or below that amount.

The researchers, who used 2002 and 2003 data from AHRQ’s Medical Expenditure Panel Survey, also found that 4.1% of families with access to employer-based health insurance were poor (family income below 100% of the federal poverty line) and 11.1% were low-income (family income 100% to 199% of the federal poverty line).

In contrast, among families without access to employer-based health insurance, 33.8% were poor and 28.4% were low income, researchers said.

The research, “Wealth, Income, and The Affordability of Health Insurance,” is published in the May/June 2009 issue of Health Affairs.