Six additional examinations have been completed every 2-5 years, including a Year 20 examination completed in 2006. Repeat measurements on traditional risk factors, including plasma lipids, blood pressure, anthropometry, smoking behavior, physical activity, and pulmonary function testing (except Years 7 and 15) have used the same methods at each examination to assess age and secular trends in these factors during young adulthood. In selected years, additional measurements have been made, including a treadmill exercise test at baseline and Year 7; diet history at baseline, Year 7, and Year 20; cardiovascular reactivity measurements in Year 2; echocardiography and ambulatory blood pressure monitoring (in a subset) at Year 5; skin reflectance and assessment of the experience of discrimination and other psychosocial measures and urine sodium and creatinine in Year 7; echocardiography (in a subset) in Year 10, glucose tolerance testing, and microalbuminuria in Year 10 and Year 20; coronary CT scan in Year 15 and Year 20; and carotid intima media thickness in Year 20.