1. National Center for Health Statistics. Prevalence of Chronic Skin and Musculoskeletal Conditions. U.S., 1969. Series 10, Number 92, 1974.
2. National Center for Health Statistics. Health Interview Survey, 1975-1976. Unpublished data, 1979.
3. National Center for Health Statistics. National Ambulatory Medical Care Survey, 1976. Unpublished data, 1979.
4. National Center for Health Statistics. Hospital Discharge Survey, 1977. Unpublished data, 1979.
5. National Safety Council. Accident Facts. Chicago, National Safety Council, 1977.