For the three screening rounds combined , with a 2-year follow-up , sensitivity was 846 % ( 95 % CI 796-892 ) , specificity was 986 % ( 95 % CI 985-988 ) , positive predictive value was 404 % ( 95 % CI 359-447 ) , and negative predictive value was 998 % ( 95 % CI 998-999 ) .