Framingham Heart Study
an ongoing large-scale, long-range survey focused on understanding, preventing, and treating cardiovascular disease. Begun in 1948, the study has involved data collection from three generations of residents of the town of Framingham, Massachusetts. The data have identified primary risk factors involved with heart disease and stroke, such as cigarette smoking, physical inactivity, obesity, high cholesterol levels, diabetes, and hypertension. The study is regarded as one of the most reliable of its kind because it is of prospective design; that is, it enrolled people who were originally free of heart disease and recorded the dietary and other habits of the participants before signs of heart disease appeared.