This paper was presented before the Research Council Scientific Forum at the 50th annual convention of the American School Health Association, New Orleans, Louisiana, October 7, 1976, and is dedicated to the memory of the late Cyrus and Barbara Mayshark who were both killed accidentally on July 24, 1976. Cyrus Mayshark was formerly Professor of Health Education and Dean of the College of Applied Life Studies at the University of Illinois.
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