Doctoral Dissertation Research: Comparing Measures of Geographic Access to Health Care in an Urban Setting

距离通常用于政策和研究，作为地理上获得保健服务的一种衡量标准。卫生保健研究强烈表明，在农村环境中，距离与卫生保健利用之间存在联系，但有证据表明，距离测量是城市环境中卫生保健获取的不可靠预测指标。地理学和旅行科学中使用的基于活动空间的地理可达性度量，将可达性表示为个人日常活动在空间和时间上的固定性，以及他们从一项活动到下一项活动的能力。这些措施可以更好地预测那些经常因缺乏交通工具或受到其他就业、经济或社会因素限制的城市个人的获取情况。本研究的目的是评估距离和活动空间为基础的措施，作为一个贫穷，城市，糖尿病人群的卫生保健可及性的空间维度的表示。具体目的是：(1)评估距离测量作为医疗保健就诊预测因子的相关性；(2)验证基于黄金标准活动空间的距离测量与地理测量的对比；(3)评估全球定位系统技术在该人群中促进数据收集的可行性。因变量和自变量将从在大型克利夫兰医疗网络中接受治疗的糖尿病患者的电子医疗记录（EMR）中获得，并从这些患者的亚样本的横断面调查中获得。随机抽取的患者样本也将被要求使用全球定位系统单位记录他们的日常旅行信息。将比较地理通道的测量，以评估它们之间的关联有多密切。多变量分析将用于确定空间访问措施与定期卫生保健就诊之间的关联。这项研究将把重点放在贫困的克利夫兰城市人口上，他们的地理可及性模式可能与现有地理可及性研究关注的农村或有车人口大不相同。本研究的结果将澄清对使用距离作为地理可达性度量的研究的解释，并可能额外指导未来在城市背景下进行的研究中度量的选择。在政策方面：政府通常依靠相当于半小时旅行时间的距离来评估地区获得医疗服务的情况，如指定卫生专业人员短缺地区。这项研究可能会提供初步的见解，说明这种方法如何很好地识别城市地区地理上较差的区域，以及如何改进它。作为博士论文研究改进奖，该奖项还将提供支持，使有前途的学生建立一个强大的独立研究生涯。

Distance is commonly used in policy and research as a measure of geographic access to health care. Studies of health care strongly suggest a link between distance and health care utilization in rural settings, but there is evidence to suggest that the distance measure is an unreliable predictor of health care access in urban settings. Activity space-based measures of geographic access, used in geography and the travel sciences, represent access as a function of the fixedness of an individual's routine in space and time, and their ability to travel from one activity to the next. These measures may better predict access for urban individuals who are more frequently constrained by lack of vehicular transportation, or are limited by other employment, economic or social considerations. The objective of this research is to evaluate distance and activity space-based measures as representations of the spatial dimensions of health care access in a poor, urban, diabetic population. Specific aims are: (1) to evaluate the relevancy of distance measures as a predictor of attendance to health care visits, (2) to validate distance measures against geographic measures based on the gold-standard activity-space, and (3) to evaluate the feasibility of global positioning system technology to facilitate data collection in this population. Dependent and independent variables will be obtained from electronic medical records (EMR) of diabetic patients that receive care in a large Cleveland health network, and from a cross-sectional survey of a subsample of those patients. A random sample of patients will also be asked to record information about their daily travel using global positioning system units. Measures of geographic access will be compared to evaluate how closely they correlate. Multivariate analysis will be used to determine the association between spatial access measures and attendance at scheduled health care visits.The study will bring focus to a poor, urban Cleveland population whose patterns of geographic access may be very different from the rural or car-owning populations that are the focus of existing geographic access research. The results of this study will clarify the interpretation of studies that use distance as a measure of geographic access, and may additionally guide the selection of measures in future studies carried out in the urban context. In terms of policy: The government often relies on distances equivalent to half-hour travel time to evaluate regional access to care, as in the designation of Health Professional Shortage Areas. This research may provide initial insight to how well this method identifies areas of poorer geographic access in urban areas, and how it might be improved. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.