Health statistics from U.S. National Health survey, series. C-4. Older persons, selected health characteristics, United States, July 1957-June 1959. selected statistics relating to limitation of activity and mobility, disability days, chronic and acute conditions, and physician and dental visits for persons 45 rears and older, based on data collected In household Interviews during July 1957-June 1959: prepared by Geraldine A. Gleeson].