The oft-cited figure of 41 million uninsured Americans is an overstatement, and a more reasonable estimate is between 21 million and 31 million, according to a report released Monday by the Congressional Budget Office.
Meanwhile, the number of Americans uninsured at any given time during a year may be close to 60 million, the report adds.
The figures come from several federally sponsored population surveys that reflect varying durations of time over which the nonelderly are uninsured.
"The uninsured population is fluid, with many people gaining and losing coverage," a report summary says. "Between half and two-thirds of the people who experienced a period of time without insurance in 1998, for example, had coverage for other portions of the year."
The CBO is a nonpartisan agency that provides Congress with economic and budget information. It estimates that between 21 million and 31 million people were insured for all of 1998, a number the office says probably has not changed since.
The commonly cited estimate of 41 million uninsured comes from the Current Population Survey (CPS) of the U.S. Census Bureau and more closely approximates the number of people who are uninsured at a specific point during the year rather than for a whole year, the CBO report says.
But data from the Survey of Income and Program Participation, also done by the Census Bureau, and the Medical Expenditures Panel Survey, done by the Agency for Healthcare Research and Quality, are gathered from multiple interviews throughout a year. The report finds that by asking people to recall their coverage over a shorter time than the CPS does, SIPP and MEPS provide more accurate estimates of the number of people who are uninsured all year.
A third set of data from SIPP and MEPS estimates the number of Americans who lack insurance at any time during the year at close to 60 million.
About 30% of nonelderly people who lose insurance at any given time remain uninsured for more than a year, while about 50% regain coverage within four months, the CBO report finds. People with less education, lower income and who are Hispanic are more likely to lack insurance and to be uninsured for longer periods of time.
The report says policies to increase insurance coverage will be most effective if they are crafted to reflect a range of estimates for the short-term and long-term uninsured.
"The fact remains that far too many Americans are uninsured," says Karen Ignani, president of the American Association of Health Plans, in a written statement. "The report also illustrates why fixing complex problems such as health care requires a targeted, multifaceted approach. There is no one-size-fits-all solution."