Finally, the VA Cooperative Study Group No. 380 did a prospective cross sectional study of 3121 asymptomatic patients between 1994-1997 to find the prevalence of advanced neoplasia and associated risk factors. 329 patients were found to have advanced neoplasia as defined by an adenoma greater than 1 cm, villous histology, presence of high-grade dysplasia, or cancer. Associations were found between advanced neoplasia and family history of CRC, smoking, moderate to heavy alcohol consumption, fiber intake, and use of daily NSAIDS or vitamin D11.