Harding Center for Risk Literacy, Max Planck Institute for Human Development, Berlin, Germany.
Ann Intern Med. 2012 Mar 6;156(5):340-9. doi: 10.7326/0003-4819-156-5-201203060-00005.
Unlike reduced mortality rates, improved survival rates and increased early detection do not prove that cancer screening tests save lives. Nevertheless, these 2 statistics are often used to promote screening.
To learn whether primary care physicians understand which statistics provide evidence about whether screening saves lives.
Parallel-group, randomized trial (randomization controlled for order effect only), conducted by Internet survey. (ClinicalTrials.gov registration number: NCT00981019)
National sample of U.S. primary care physicians from a research panel maintained by Harris Interactive (79% cooperation rate).
297 physicians who practiced both inpatient and outpatient medicine were surveyed in 2010, and 115 physicians who practiced exclusively outpatient medicine were surveyed in 2011.
Physicians received scenarios about the effect of 2 hypothetical screening tests: The effect was described as improved 5-year survival and increased early detection in one scenario and as decreased cancer mortality and increased incidence in the other.
Physicians' recommendation of screening and perception of its benefit in the scenarios and general knowledge of screening statistics.
Primary care physicians were more enthusiastic about the screening test supported by irrelevant evidence (5-year survival increased from 68% to 99%) than about the test supported by relevant evidence (cancer mortality reduced from 2 to 1.6 in 1000 persons). When presented with irrelevant evidence, 69% of physicians recommended the test, compared with 23% when presented with relevant evidence (P < 0.001). When asked general knowledge questions about screening statistics, many physicians did not distinguish between irrelevant and relevant screening evidence; 76% versus 81%, respectively, stated that each of these statistics proves that screening saves lives (P = 0.39). About one half (47%) of the physicians incorrectly said that finding more cases of cancer in screened as opposed to unscreened populations "proves that screening saves lives."
Physicians' recommendations for screening were based on hypothetical scenarios, not actual practice.
Most primary care physicians mistakenly interpreted improved survival and increased detection with screening as evidence that screening saves lives. Few correctly recognized that only reduced mortality in a randomized trial constitutes evidence of the benefit of screening.
Harding Center for Risk Literacy, Max Planck Institute for Human Development.
与降低死亡率不同，生存率的提高和早期检测的增加并不能证明癌症筛查测试能拯救生命。尽管如此，这两个统计数据经常被用来推广筛查。
了解初级保健医生是否理解哪些统计数据提供了关于筛查是否能拯救生命的证据。
通过互联网调查进行平行组、随机试验（仅按随机顺序控制随机分组）。（临床试验.gov 注册号：NCT00981019）
哈里斯互动公司（Harris Interactive）维护的美国初级保健医生研究小组的全国样本（合作率为 79%）。
2010 年调查了 297 名同时从事住院和门诊医疗的医生，2011 年调查了 115 名仅从事门诊医疗的医生。
医生收到了两个假设筛查测试效果的情况：一种情况描述为 5 年生存率提高，早期检测增加，另一种情况描述为癌症死亡率降低，发病率增加。
医生在这些情况下对筛查的建议以及对其益处的看法，以及对筛查统计数据的一般了解。
初级保健医生对支持不相关证据的筛查测试（5 年生存率从 68%提高到 99%）比对支持相关证据的测试（1000 人中癌症死亡率从 2 降至 1.6）更感兴趣。当呈现不相关的证据时，69%的医生建议进行测试，而当呈现相关证据时，只有 23%的医生建议进行测试（P < 0.001）。当被问及有关筛查统计数据的一般知识问题时，许多医生无法区分不相关和相关的筛查证据；分别有 76%和 81%的医生表示，这些统计数据中的每一个都证明了筛查能拯救生命（P = 0.39）。大约一半（47%）的医生错误地说，在筛查人群中发现更多的癌症病例“证明了筛查能拯救生命”。
医生对筛查的建议是基于假设的情况，而不是实际的做法。
大多数初级保健医生错误地将筛查的生存改善和检测增加解释为筛查能拯救生命的证据。很少有人正确地认识到，只有随机试验中死亡率的降低才能构成筛查益处的证据。
哈丁风险素养中心，马克斯·普朗克人类发展研究所。
