Subjects were selected by simple random sampling. Data were collected on dependent variables including blood pressure, heart rate, echocardiography, Doppler flow, blood lipids, and smoking. Independent variables included growth, diet and nutrition, electrolytes, physical activity and fitness, personal, family, and social history, and bone age. Most observations were recorded at four month intervals. There was a six month pretest recruitment period, four years of cycled measurements and data collection, and six months of analysis and reporting. Curves for both velocity and acceleration of growth for attained levels of blood pressure, blood lipids, and smoking were determined as were longitudinal relationships between individual growth curves of blood pressure, echocardiographic measures, physical growth, sexual maturation, body composition, diet, physical activity, and social factors.