MODELING SPATIAL ACCESSIBILITY TO LOWER ENDOSCOPY SERVICES IN THE UNITED STATES

简介(申请人提供)：结直肠癌(CRC)是美国第四大常见癌症，也是导致癌症死亡的第二大原因。较低的内窥镜检查，包括柔性乙状结肠镜和结肠镜检查，已经被证明可以通过检测和切除癌前病变和早期发现结直肠癌来降低发生结直肠癌的风险和结直肠癌特有的死亡率。然而，在50岁或50岁以上的人群中，较低的内窥镜使用率仍然不到60%。先前的研究发现，在结直肠癌筛查、发病率和存活率方面存在显著的地理差异。小范围的社会经济剥夺与儿童权利公约相关的结果有关，但无法解释观察到的儿童权利相关结果的地理差异，这表明其他社区特征导致儿童权利相关结果的地理差异。获得医疗保健是获得优质医疗服务的重要先决条件，因此也是健康结果的决定因素。乳房X光检查服务的空间可及性低与晚期乳腺癌的风险增加有关。较低的内窥镜检查服务的空间可及性是否会导致结直肠癌相关预后的地理差异，目前知之甚少。因此，我们将探索这样一个假设，即结直肠癌筛查、发病率和存活率的地理差异可归因于较低的内窥镜服务的空间可及性。将解决两个具体目标：(1)使用地理信息系统、医疗保险数据和空间统计建模，计算和绘制全美包括50个州和华盛顿特区在内的较低内窥镜服务的小区域空间可及性，以及(2)检查较低的内窥镜服务的小区域空间可及性对与CRC相关的结果的影响，包括事件CRC的风险、诊断的晚期以及特定于CRC的死亡率。我们将使用三种不同的空间方法，根据使用医疗保险数据进行乙状结肠镜检查或结肠镜检查的医生的位置，量化和绘制小区域空间可及性，以降低内窥镜检查服务。然后，我们将把小区域的空间无障碍措施与高质量的NIH-AARP饮食和健康研究的数据联系起来，包括566,407人，以前瞻性地评估较低的内窥镜服务的空间无障碍对结直肠癌发病率、晚期诊断和结直肠癌特定死亡率的影响。这是第一次研究较低的内窥镜检查服务的空间可及性的地理差异，并前瞻性地评估其对结直肠癌预后的影响。拟议的研究结果将为循证多水平干预措施的开发和实施提供证据，以增加较低的内窥镜使用率，从而改善与结直肠癌相关的结果。此外，拟议的研究将开发空间可及性地图，这将帮助地方和州政策制定者改善低位内窥镜服务的分配。

DESCRIPTION (provided by applicant): Colorectal cancer (CRC) is the fourth most common cancer and the second leading cause of cancer deaths in the United States. Lower endoscopic examinations including flexible sigmoidoscopy and colonoscopy have been demonstrated to reduce the risks of incident CRC and CRC-specific mortality through detection and removal of precancerous lesions and early detection of CRC. However, lower endoscopy utilization is still less than 60% among persons aged 50 years or older. Previous research identified significant geographic variations in CRC screening, incidence, and survival. Small-area socioeconomic deprivation has been associated with CRC-related outcomes, but was unable to explain the observed geographic disparity in CRC-related outcomes, suggesting that other community-level characteristics contribute to geographic disparities in CRC-related outcomes. Access to healthcare is an important prerequisite to obtaining quality care and thus a determinant of health outcomes. Low spatial accessibility to mammography service has been associated with an increased risk of late-stage breast cancer. Little is known whether spatial accessibility to lower endoscopy services contributes to the geographic variation in CRC-related outcomes. Therefore, we will explore the hypothesis that geographic disparities in CRC screening, incidence and survival are attributable to spatial accessibility to lower endoscopy services. Two specific aims will be addressed: (1) Compute and map small-area spatial accessibility to lower endoscopy services across the United States including 50 states and Washington DC, using a GIS, Medicare data, and spatial statistical modeling, and (2) Examine the effects of small-area spatial accessibility to lower endoscopy services on CRC-related outcomes, including the risks of incident CRC, advanced stage at diagnosis, and CRC-specific mortality. We will use three different spatial approaches to quantify and map small-area spatial accessibility to lower endoscopy services based on the locations of physicians who performed a sigmoidoscopy or colonoscopy using Medicare data. Then, we will link the small-area spatial accessibility measures with data from the high- quality NIH-AARP Diet and Health Study including 566,407 persons to prospectively assess the effects of spatial accessibility to lower endoscopy services on CRC incidence, advanced stage at diagnosis and CRC- specific mortality. This is the first study to examine the geographic disparity in spatial accessibility to lower endoscopy services and prospectively evaluate its effect on CRC outcomes. The results of the proposed study will provide evidence for the development and implementation of evidence-based multilevel interventions to increase lower endoscopy use and thus improve CRC-related outcomes. In addition, the proposed study will develop a spatial accessibility map which will help local and state policy makers improve the allocation of lower endoscopy services.