If all states offered the same quality of health care to children as did Iowa, Vermont, Maine, Massachusetts and New Hampshire, 4.6 million more children in the nation would have health insurance, a new report suggests.

The report from the Commonwealth Fund, New York, ranked those 5 states at the top in the quality of health care available to their youngest residents.

Lowest-ranked states for children’s health care were Arizona, Louisiana, Mississippi, Florida and Oklahoma.

The rankings were based on 13 measures, grouped under 5 performance dimensions: access, quality, costs, potential to lead healthy lives and equity. The last component measured access to care in relation to income, race-ethnicity and insurance coverage.

Conditions measured included percentage of children who were insured and rates of infant mortality, vaccinations, preventive care, developmental delays, medical spending levels and outcomes of medical treatments.

Despite federal and state programs to assure health insurance coverage for children, the report found some states do much better than others in promoting the health and mental development of their children.

The Commonwealth Fund authors–Katherine Shea, Karen Davis and Edward Schor–contend that top-ranked states show high performance is possible. For instance, Iowa and Vermont had developed children’s health care system that put outstanding care within reach of most children, regardless of such demographic attributes as income. At the same times, these programs controlled spending and the cost of family health care premiums. Both states expanded their State Children’s Health Insurance Program, which was enacted by Congress in 1997 to increase coverage of children in low-income families.

The Commonwealth Fund also found that states in the top quartile of best-performing states in general rated highly on several indicators, including having relatively low uninsured rates for children. In addition to the top 5, these states included Ohio, Hawaii, Rhode Island and Kentucky.

The states at the bottom quartile lagged well behind top states in such quality indicators as infant mortality, risk of development delay and percent covered by insurance. These lower-ranked states included Texas, Illinois, New Mexico, Alaska, New Jersey and Oregon.

The proportion of children who are uninsured ranged from a low of 5% in Michigan to a high of 20% in Texas, the researchers found. The ratio of children having regular medical and dental preventive care ranged from 75% in Massachusetts to 46% in Idaho, while the proportion hospitalized for asthma varied from 55 per 100,000 children in Vermont to 314 per 100,000 in South Carolina, among 33 states reporting this figure.

To help gauge excellence of care, the report also used the concept of the medical home, which is a health care provider that gives each member a preventive-care visit annually, provides access to urgent care and to specialists when needed, and provides other essential health services.

The Fund found 61% of children in New Hampshire and over half of all children in all the New England States have a medical home, compared with only a third of those in Mississippi.

The authors found ample opportunities for all states to improve health care for children, including in those states they rated highly.

Across all states, 65% of uninsured and 51% of poor people did not receive recommended levels of medical and dental care, while only 37% of insured children and 30% of higher-income children failed to get those services.

As for developmental problems, 33% of young children in Louisiana were at moderate to high risk for developmental lags compared to 16% of young children in Vermont.

State per-capita spending ranged from $8,295 a person in Washington, D.C. to $3,972 a person in Utah. Employer-sponsored family premiums ranged from $8,334 in North Dakota to $11,924 in Rhode Island.

Stephen C. Schoenbaum, executive vice president for programs and executive director of the Fund’s Commission on a High Performance Health System, says the study points to increased availability of health care insurance as one route to improved care–and not just for children, Schoenbaum notes.

He suggests health insurers could help reduce variations in health care among states by advocating universal coverage and by providing coverage aimed at increasing the use of medical homes.

“A fairly significant percentage of Americans don’t have a medical home,” he says. “A medical home provides not just primary care but also makes coordinated care accessible. Members can call 24-7 and not just get an answering service.”

He thinks insurers need to think of ways to pay for medical home services that currently aren’t offered to their members.

“Insurers need to see this as being to their advantage,” Schoenberg says.

Insurers might also improve health care by using their own record-keeping systems to facilitate immunizations and other preventive care, he suggests.

“From claims filed, they can determine who hasn’t had their shots and can send reminders to physicians and patients about immunizations needed as well as mammograms and so on,” he says

Other measures insurers can take to improve health care access is to provide more health education, Schoenbaum says. He would also like to see insurers pay for more developmental screenings, which measure a child’s mental and physical progress.

A spokesman for America’s Health Insurance Plans, Washington, notes that the Commonwealth report was one of a number of recent studies looked at variations in health care among the states.

“Our industry looks at this as top priority,” said the spokesman, Robert Zirkelbach. “We need to get everybody in the system and get everyone covered.”

AHIP also announced it was preparing to release a new national strategy proposal to reduce health care costs and make health care coverage more affordable for consumers and employers.

AHIP says the strategy grew out of proposals from its board of directors to cover the uninsured, improve the quality and safety of health care, and to guarantee access to health care coverage in the individual market.