Jackson, Ann L. <i>Children and Youth : Selected Health Characteristics, United States - 1958 and 1968 : Selected Statistics Based On Data Collected In Household Interviews Relating to the Extent of Illness and Disability, the Use of Medical Services, and Health Insurance Coverage by Age, with Emphasis On the Health Status of Persons Under 25 Years of Age.</i> Rockville, Maryland: U.S. Department of Health, Education, and Welfare, Public Health Service, Health Services and Mental Health Administration, National Center for Health Statistics, 1971.