The Utah Department of Health estimates the number at nearly 378,000, including more than 56,000 under 19 eligible for the state's Children's Health Insurance Program.
The 2010 uninsured rate was 10.6 percent, though officials say improved survey methods to include cellphone users may account for the difference.
Among self-employed residents, 29 percent reported being uninsured. About 26 percent of adults who worked only part time went without insurance. Adults 19-34 were the most likely to go without insurance.
Utah Department of Health Executive Director David Patton says he was discouraged so many youngsters living below 200 percent of the federal poverty level went uninsured when a state program for children "could have helped them."
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