Documents the Fels longitudinal study, a study of human growth maturation and body composition. The book shows how data collected from more than 1,000 participants during the past 60 years have been analyzed to test a wide range of hypotheses, and describes how the findings have led to the development of improved research methods. Topics covered include: the management and analysis of data; prenatal, familial and genetic studies; physical growth, development and maturation; bones and teeth; body composition; and risk factors for cardiovascular diseases.