丹麦学者报道他们进行了一项为期10年的大数量、随机分组的普查研究，对象为45－75岁的人群。每两年进行一次大便潜血试验的结直肠癌普查，结果使该病的死亡率有所下降。纳入随机分组普查的人群为30968名，其中20672名（67％）完成了第一轮普查，90％的人乐于接受以后的继续检 Danish scholars reported that they had conducted a large-scale, randomized, census study for 10 years, targeting 45-75-year-olds. A general survey of colorectal cancer with a fecal occult blood test every two years has resulted in a reduction in the mortality rate of the disease. A total of 30,968 people were included in the randomized censuses, among which 20,672 (67%) completed the first round of census, and 90% were willing to accept further follow-up tests.