Kowalski Amanda E
Department of Economics, University of Michigan.
Rev Econ Stud. 2023 Jan;90(1):432-462. doi: 10.1093/restud/rdac022. Epub 2022 May 9.
Mammography guidelines have weakened in response to evidence that mammograms diagnose breast cancers that would never eventually cause symptoms, a phenomenon called "overdiagnosis." Given concerns about overdiagnosis, instead of recommending mammograms, US guidelines encourage women aged 40-49 to get them as they see fit. To assess whether these guidelines target women effectively, I propose an approach that examines mammography behavior within an influential clinical trial that followed participants long enough to find overdiagnosis. I find that women who are more likely to receive mammograms are healthier and have higher socioeconomic status. More importantly, I find that the 20-year level of overdiagnosis is at least 3.5 times higher among women who are most likely to receive mammograms. At least 36% of their cancers are overdiagnosed. These findings imply that US guidelines encourage mammograms among healthier women who are more likely to be overdiagnosed by them. Guidelines in other countries do not.
鉴于有证据表明乳房X光检查会诊断出那些最终不会引发症状的乳腺癌，即所谓的“过度诊断”现象，乳房X光检查指南的力度已经有所减弱。出于对过度诊断的担忧，美国指南不再推荐进行乳房X光检查，而是鼓励40至49岁的女性根据自身情况自行决定是否进行检查。为了评估这些指南是否有效地针对了女性群体，我提出了一种方法，该方法通过一项有影响力的临床试验来研究乳房X光检查行为，该试验对参与者进行了足够长时间的跟踪，以发现过度诊断情况。我发现，更有可能接受乳房X光检查的女性更健康，社会经济地位也更高。更重要的是，我发现，在最有可能接受乳房X光检查的女性中，20年的过度诊断水平至少高出3.5倍。她们至少36%的癌症被过度诊断。这些发现意味着美国指南鼓励更健康的女性进行乳房X光检查，而这些女性更有可能被过度诊断。其他国家的指南则并非如此。
