Computer glitches on the government's health insurance website, Healthcare.gov, have created nightmarish experiences for thousands of Americans trying to buy health coverage under the new federal health law. But there may be a second reason why so many have struggled: Fully half of uninsured Americans have never tried to shop for health insurance in the individual market, according to a study released Wednesday. And nearly half of the target population for the Affordable Care Act report having had negative experiences in the past when trying to buy coverage in the non-group market.

Only a small number of people buy health insurance in the individual market in any given year, because most Americans are covered by employer group plans or by the government programs Medicare and Medicaid.

But the study, conducted by the Urban Institute in Washington, D.C., also offered glimmers of hope for those who are uninsured. More than 60 percent of the target population who had tried to buy health insurance in the past said that cost was the main barrier. The Affordable Care Act offers free coverage to consumers who qualify for Medicaid and subsidies to buy private insurance for millions more whose incomes are too high to qualify for Medicaid.

"The data reaffirm the fact that cost is the major reason why people go without health insurance,'' said Kathy Hempstead of the Robert Wood Johnson Foundation, which helped fund the Urban Institute research. "Outreach efforts need to highlight the availability of reasonably priced plans in the (online) marketplaces, and the existence of subsidies that help many people purchase plans."

--DAVID HAGE