Spatial agglomeration in the use of emergency telephone consultation services in a prefecture of Japan: a geographic information system-based spatial statistical analysis

Emergency telephone consultation (ETC) services are telephone triage systems used in emergency care. The number of local governments introducing these services has gradually increased in Japan, and approximately 47% of the population can access it. However, ETC use is known to be low in Japan and may be unevenly distributed among municipalities. This study examines the spatial agglomeration of ETC use with spatial statistical analysis. This study evaluated ETC service users during the first year of its introduction in Saitama Prefecture, Japan (2014–2015). The number of age-adjusted ETC service users per 1,000 individuals by municipality during the observational period was calculated by the direct method, using the 2015 Model Population of Japan as the standard. The spatial patterns of ETC service usage were analyzed using spatial autocorrelation and hot spot analyses. Based on hot spot analysis, municipalities were categorized as hot spots, cold spots, and intermediate (other) spots. The population density of the three groups was analyzed by multiple comparisons. Overall, 22,073 ETC users were recorded during the study period. After excluding users with missing information, 15,257 users (69%) (median age = 43 [interquartile range: 32–61] years, men = 44%) were included in the analysis. The mean number of age-adjusted ETC service users per 1,000 individuals by municipality was 1.8 (range: 0.13–4.31). Spatial autocorrelation analysis revealed spatial agglomeration in ETC use (Global Moran’s I = 0.58, z-score = 7.27, p < 0.001). Hot spot analysis detected hot and cold spots in municipalities in the eastern (urban cities) and western (mountainous areas) parts of the prefecture, respectively. The hot spot areas exhibited significantly higher population density than the intermediate and cold spot areas (p = 0.009 and p < 0.001, respectively). The use of ETC services was higher in urban areas than in mountainous areas. Further research is required to determine the causes of the uneven regional distribution of ETC use. However, these findings offer insights into strategies for promoting ETC services in different areas. Increased publicity activities are required in the mountainous areas to encourage residents to use ETCs.