Viertel Centre for Research in Cancer Control, Cancer Council Queensland, PO Box 201, Spring Hill QLD 4004, Australia.
BMC Cancer. 2010 Jan 28;10:24. doi: 10.1186/1471-2407-10-24.
In Australia, associations between geographic remoteness, socioeconomic disadvantage, and colorectal cancer (CRC) survival show that survival rates are lowest among residents of geographically remote regions and those living in disadvantaged areas. At present we know very little about the reasons for these inequalities, hence our capacity to intervene to reduce the inequalities is limited.
METHODS/DESIGN: This study, the first of its type in Australia, examines the association between CRC survival and key area- and individual-level factors. Specifically, we will use a multilevel framework to investigate the possible determinants of area- and individual-level inequalities in CRC survival and quantify the relative contribution of geographic remoteness, socioeconomic and demographic factors, disease stage, and access to diagnostic and treatment services, to these inequalities. The multilevel analysis will be based on survival data relating to people diagnosed with CRC in Queensland between 1996 and 2005 (n = 22,723) from the Queensland Cancer Registry (QCR), area-level data from other data custodians such as the Australian Bureau of Statistics, and individual-level data from the QCR (including extracting stage from pathology records) and Queensland Hospitals. For a subset of this period (2003 and 2004) we will utilise more detailed, individual-level data (n = 1,966) covering a greater range of risk factors from a concurrent research study. Geo-coding and spatial technology will be used to calculate road travel distances from patients' residence to treatment centres. The analyses will be conducted using a multilevel Cox proportional hazards model with Level 1 comprising individual-level factors (e.g. occupation) and level 2 area-level indicators of remoteness and area socioeconomic disadvantage.
This study focuses on the health inequalities for rural and disadvantaged populations that have often been documented but poorly understood, hence limiting our capacity to intervene. This study utilises and develops emerging statistical and spatial technologies that can then be applied to other cancers and health outcomes. The findings of this study will have direct implications for the targeting and resourcing of cancer control programs designed to reduce the burden of colorectal cancer, and for the provision of diagnostic and treatment services.
在澳大利亚，地理偏远程度、社会经济劣势与结直肠癌（CRC）生存之间的关联表明，居住在地理偏远地区和处于不利地区的居民的生存率最低。目前，我们对造成这些不平等现象的原因知之甚少，因此，我们干预以减少不平等现象的能力有限。
方法/设计：本研究在澳大利亚尚属首例，旨在检验 CRC 生存与关键地区和个体层面因素之间的关联。具体而言，我们将使用多层次框架来研究 CRC 生存的地区和个体不平等现象的可能决定因素，并量化地理偏远程度、社会经济和人口因素、疾病分期以及诊断和治疗服务的获取对这些不平等现象的相对贡献。该多层次分析将基于昆士兰癌症登记处（QCR）中在 1996 年至 2005 年期间诊断为 CRC 的人群的生存数据（n=22723），这些数据来自其他数据保管人，如澳大利亚统计局的地区数据，以及 QCR 的个体数据（包括从病理记录中提取分期）和昆士兰医院。在该时期的一个子集中（2003 年和 2004 年），我们将利用来自同期研究的更详细的个体层面数据（n=1966），涵盖更广泛的风险因素。地理编码和空间技术将用于计算从患者居住地到治疗中心的道路旅行距离。分析将使用包含个体层面因素（如职业）的多层次 Cox 比例风险模型进行，第 1 层包含个体层面因素，第 2 层包含偏远地区和地区社会经济劣势的区域指标。
本研究侧重于经常被记录但理解欠佳的农村和弱势群体的健康不平等现象，因此限制了我们干预的能力。本研究利用并开发了新兴的统计和空间技术，然后可以将这些技术应用于其他癌症和健康结果。本研究的结果将对旨在减少结直肠癌负担的癌症控制计划的目标制定和资源配置直接产生影响，也将对诊断和治疗服务的提供产生影响。
