Gates T J
Department of Family and Community Medicine, Lancaster General Hospital, Pennsylvania 17604, USA.
Am Fam Physician. 2001 Feb 1;63(3):513-22.
Many patients expect to undergo screening tests for cancer. In evaluating screening procedures, physicians must take into account the known effects of lead time, length and screening biases, all of which can result in an overestimation of the benefits of screening. The gold standard by which a screening test is evaluated remains the prospective, randomized controlled trial, demonstrating reduced morbidity and mortality. The magnitude of benefit from screening is best expressed in terms of the number of patients needed to screen. This value ranges from approximately 500 to 1,100 for proven screening interventions. These concepts are illustrated by controversies in current screening recommendations for cancers of the cervix, lung, colon, breast and prostate, which together account for more than 50 percent of cancer deaths in the United States.
许多患者期望接受癌症筛查测试。在评估筛查程序时，医生必须考虑到已知的领先时间、长度和筛查偏倚的影响，所有这些都可能导致对筛查益处的高估。评估筛查测试的金标准仍然是前瞻性随机对照试验，证明发病率和死亡率降低。筛查的益处大小最好用需要筛查的患者数量来表示。对于已证实的筛查干预措施，这个值大约在500到1100之间。美国目前针对宫颈癌、肺癌、结肠癌、乳腺癌和前列腺癌的筛查建议中的争议就说明了这些概念，这些癌症加起来占美国癌症死亡人数的50%以上。
