... N Engl J Med 2006; 355:1572-1582October 12, 2006DOI: 10.1056/NEJMsa060185. ... of 26 collaborating CCSS institutions; a date of diagnosis between January 1, 1970, and December 31, 1986; an age of ... a risk of having a condition of grade 3 or 4 that was at least 10 times the ...