Applying a spatial analysis method for epidemiological studies: Advancing public health research with geographically weighted Poisson regression (GWPR) using R

Authors

  • Saksin Simsin Lecturer, Faculty of Public Health, University of Phayao

Keywords:

Geographically weighted Poisson regression, Spatial health data analysis, Public health research, Spatial statistical method

Abstract

     Public health research increasingly involves spatial analysis to identify disease patterns, assess context-specific risk factors, and inform evidence-based decision-making for specific areas. However, conventional statistical models such as Poisson regression assume spatial stationarity, limiting their ability to compute for geographic heterogeneity in the relationships between health outcomes and explanatory variables. This paper introduces geographically weighted Poisson regression (GWPR) as an
advanced spatial analytical technique that addresses these limitations by allowing regression coefficients to vary across each spatial unit of the study region, enabling the identification of localized patterns of disease occurrence and influencing risk factors. By incorporating spatial weighting based on specified kernel functions and localized parameter estimation, GWPR enables the identification of region-specific associations and enhances the accuracy of epidemiological modeling. This review article elucidates the theoretical foundation of GWPR, its methodological framework, and its application in public health research, along with a comprehensive, step-by-step guide for implementing GWPR in R. The guide includes data preparation, bandwidth optimization, model fitting, diagnostics, and visualization of spatially varying coefficients. By making GWPR more accessible to researchers and public health practitioners, this method can be effectively integrated into real-world spatial health data analysis. Ultimately, it supports the development of targeted, data-driven public health strategies based on robust, location-specific evidence.

References

Brunsdon, C., Fotheringham, A. S., & Charlton, M. E. (1996). Geographically weighted regression: A method for exploring spatial nonstationarity. Geographical Analysis, 28(4), 281–298.

Bui, L. V., Mor, Z., Chemtob, D., Ha, S. T., & Levine, H. (2018). Use of geographically weighted Poisson regression to examine the effect of distance on tuberculosis incidence: A case study in Nam Dinh, Vietnam. PLOS ONE, 13(11), e0207068. https://doi.org/10.1371/journal.pone.0207068

Comber, A., Brunsdon, C., Charlton, M., Dong, G., Harris, R., Lu, B., Lü, Y., Murakami, D., Nakaya, T., Wang, Y., & Harris, P. (2020, April 13). The GWR route map: A guide to the informed application of geographically weighted regression. arXiv. Retrieved March 10, 2025 From https://arxiv.org/abs/2004.06070

Fotheringham, A. S., Brunsdon, C., & Charlton, M. (2002). Geographically weighted regression: The analysis of spatially varying relationships. Wiley.

Fotheringham, A. S., Brunsdon, C., & Charlton, M. E. (2009). Geographically weighted regression. The Sage handbook of spatial analysis, 1, 243-254.

Fundisi, E., Dlamini, S., Mokhele, T., Weir-Smith, G., & Motolwana, E. (2023). Exploring determinants of HIV/AIDS self-testing uptake in South Africa using generalized linear Poisson and geographically weighted Poisson regression. Healthcare, 11(6), 881. https://doi.org/10.3390/healthcare11060881

Hadayeghi, A., Shalaby, A. S., & Persaud, B. N. (2010). Development of planning level transportation safety tools using geographically weighted Poisson regression. Accident Analysis & Prevention, 42(2), 676-688.

Helmy, H., Kamaluddin, M. T., Iskandar, I., & Suheryanto. (2022). Investigating spatial patterns of pulmonary tuberculosis and main related factors in Bandar Lampung, Indonesia using geographically weighted Poisson regression. Tropical Medicine and Infectious Disease, 7(9), 212.

Kirby, R. S., Delmelle, E., & Eberth, J. M. (2017). Advances in spatial epidemiology and geographic information systems. Annals of Epidemiology, 27(1), 1-9. https://doiorg/10.1016/j.annepidem.2016.12.001

Kulldorff, M. (1997). A spatial scan statistic. Communications in Statistics-Theory and Methods, 26(6), 1481-1496.

Li, G., Wang, S., Liu, X., Bigham, J. M., & Ragland, D. R. (2013). Using geographically weighted Poisson regression for countylevel crash modeling in California. Safety Science, 58, 89-97.

McMillen, D. P. (2004). Geographically weighted regression: The analysis of spatially varying relationships. Journal of Regional Science, 44(1), 1-22.

Munira, S., & Sener, I. N. (2020). A geographically weighted regression model to examine the spatial variation of the socioeconomic and land-use factors associated with Strava bike activity in Austin, Texas. Journal of Transport Geography, 88, 102865. https://doi.org/10.1016/j.jtrangeo.2020.102865

Murakami, D., Tsutsumida, N., Yoshida, T., Nakaya, T., Lu, B., & Harris, P. (2023). A linearization for stable and fast geographically weighted Poisson regression. International Journal of Geographical Information Science, 37(8), 1818-1839.

Nakaya, T., Fotheringham, A. S., Brunsdon, C., & Charlton, M. (2005). Geographically weighted Poisson regression for disease association mapping. Statistics in Medicine, 24(17), 2695-2717.

Poliart, A., Kirakoya-Samadoulougou, F., Ouédraogo, M., Collart, P., Dubourg, D., & Samadoulougou, S. (2021). Using geographically weighted Poisson regression to examine the association between socioeconomic factors and hysterectomy incidence in Wallonia, Belgium. BMC Women’s Health, 21(1), 373.

Saefuddin, A., Saepudin, D., & Kusumaningrum, D. (2013). Geographically weighted Poisson regression (GWPR) for analyzing the

malnutrition data in Java-Indonesia. Procedia Social and Behavioral Sciences, 101, 100-108.

Tobler, W. R. (1970). A computer movie simulating urban growth in the Detroit region. Economic Geography, 46(sup1), 234-240.

Tyas, S. W., Gunardi, & Puspitasari, L. A. (2023). Geographically weighted generalized Poisson regression model with the best

kernel function in the case of the number of postpartum maternal mortality in East Java. Methods X, 10, 102002. https://doi.org/10.1016/j.mex.2023.102002

Wheeler, D. C. (2021). Geographically weighted regression. In M. M. Fischer & P. Nijkamp (Eds.), Handbook of regional science (pp.1895-1921). Springer.

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Published

2025-12-28

How to Cite

Simsin, S. (2025). Applying a spatial analysis method for epidemiological studies: Advancing public health research with geographically weighted Poisson regression (GWPR) using R. Journal of Public Health and Health Sciences Research, 7(3), 1–19. retrieved from https://he01.tci-thaijo.org/index.php/JPHSR/article/view/278027