77 million people U.S. Department of Health & Human Services http://www.health.gov/communication/literacy/issuebrief/ Only about 12 percent study www.health.gov/communication/literacy/issuebrief/ U.S. Department of Health & Human Services U.S. Department of Health & Human Services http://www.health.gov/communication/literacy/issuebrief/ U.S. Department of Health & Human Services survey of health literacy U.S. Department of Health & Human Services www.health.gov/communication/literacy/issuebrief/ http://www.health.gov/communication/literacy/issuebrief U.S. Department of Health & Human Services http://health.gov/communication/literacy/issuebrief/ U.S. Department of Health & Human Services http://www.health.gov/communication/literacy/issuebrief/ http://www.health.gov/communication/literacy/issuebrief/ U.S. Department of Health & Human Services America's Health Literacy http://www.health.gov/communication/literacy/issuebrief/ survey of health literacy U.S. Department of Health & Human Services Office of Disease Prevention and Health Promotion study survey of health literacy 77 million people U.S. Department of Health & Human Services basic or below basic health literacy 77 million people study http://www.health.gov/communication/literacy/issuebrief/ National Assessment of Adult Literacy study