Department of Health Data Science, Yokohama City University, Yokohama, Japan
Department of Health Policy Science, Yamagata University, Yamagata, Japan.
BMJ Open. 2023 Jun 19;13(6):e068800. doi: 10.1136/bmjopen-2022-068800.
Rural-urban healthcare disparities exist globally. Various countries have used a rurality index for evaluating the disparities. Although Japan has many remote islands and rural areas, no rurality index exists. This study aimed to develop and validate a Rurality Index for Japan (RIJ) for healthcare research.
We employed a modified Delphi method to determine the factors of the RIJ and assessed the validity. The study developed an Expert Panel including healthcare professionals and a patient who had expertise in rural healthcare.
The panel members were recruited from across Japan including remote islands, mountain areas and heavy snow areas. The panel recruited survey participants whom the panel considered to have expertise.
The initial survey recruited 100 people, including rural healthcare providers, local government staff and residents.
Factors to include in the RIJ were identified by the Expert Panel and survey participants. We also conducted an exploratory factor analysis on the selected factors to determine the factor structure. Convergent validity was examined by calculating the correlation between the index for physician distribution and the RIJ. Criterion-related validity was assessed by calculating the correlation with average life expectancy.
The response rate of the final survey round was 84.8%. From the Delphi surveys, four factors were selected for the RIJ: population density, direct distance to the nearest hospital, remote islands and whether weather influences access to the nearest hospital. We employed the factor loadings as the weight of each factor. The average RIJ of every zip code was 50.5. The correlation coefficient with the index for physician distribution was -0.45 (p<0.001), and the correlation coefficients with the life expectancies of men and women were -0.35 (p<0.001) and -0.12 (p<0.001), respectively.
This study developed the RIJ using a modified Delphi method. The index showed good validity.
城乡医疗保健差距在全球范围内存在。各国都使用农村指数来评估这种差距。尽管日本有许多偏远岛屿和农村地区，但没有农村指数。本研究旨在开发和验证日本农村指数（RIJ）用于医疗保健研究。
我们采用改良德尔菲法确定 RIJ 的因素，并评估其有效性。该研究成立了一个专家小组，包括医疗保健专业人员和一名对农村医疗保健有专长的患者。
小组成员来自日本各地，包括偏远岛屿、山区和多雪地区。专家组招募了他们认为具有专长的调查参与者。
初步调查招募了 100 人，包括农村医疗保健提供者、地方政府工作人员和居民。
专家小组和调查参与者确定了 RIJ 中包含的因素。我们还对选定的因素进行了探索性因子分析，以确定因子结构。通过计算医师分布指数与 RIJ 之间的相关性来检验收敛有效性。通过计算与平均预期寿命的相关性来评估与标准相关的有效性。
最终调查轮次的回复率为 84.8%。从德尔菲调查中，选择了四个因素用于 RIJ：人口密度、到最近医院的直接距离、偏远岛屿以及天气是否影响到最近医院的可达性。我们使用因子负荷作为每个因素的权重。每个邮政编码的平均 RIJ 为 50.5。与医师分布指数的相关系数为-0.45（p<0.001），与男性和女性预期寿命的相关系数分别为-0.35（p<0.001）和-0.12（p<0.001）。
本研究使用改良德尔菲法开发了 RIJ。该指数具有良好的有效性。
