BMC Public Health 2005, 5:65 http://www.biomedcentral.com/1471-2458/5/65 activities will contribute to improving the health status of older people and prolongation of healthy longevity, espe- cially in urban areas. Although we addressed HE in this study, the results sug- gest that disability prevalence (SCR) is a useful indicator independently of mortality data including LE. Since HE was estimated using LE and SCR, the difference in the rela- tion with socio-demographic indicators between LE and HE implies that SCR includes quite different dimensions from LE. The use of long-term care prevalence, in combi- nation with mortality indicators (e.g., LE) and compre- hensive indicators (e.g., HE), will contribute to concrete health policy making and evaluation for improvement of health, well-being, and quality of life in elderly population. Conclusion This study established a method to estimate HE available at the local level using a linear regression formula with life expectancy and long-term care prevalence. Municipal HE65 (years) ranged from 13.13 to 17.39 for men and from 14.84 to 20.53 for women. As a result of correlation analysis, a decreased HE was associated with higher per- centage of households of a single elderly person and divorce rate, and lower socioeconomic conditions. This study suggests that older people in urban areas are suscep- tible to socio-demographic factors, and a social support network for older people living in socioeconomically dis- advantaged conditions should be encouraged. Competing interests The author(s) declare that they have no competing interests. Authors' contributions YF designed the study, analyzed the data, and drafted the article. KN helped to interpret the results and edited the draft. TT supervised the data analysis and writing the article. Additional material Additional File 1 Calculation of Bayesian SCR. Calculation of standardized certification ratio (SCR) using Bayesian hierarchical Poisson regression Click here for file [http://www.biomedcentral.com/content/supplementary/1471- 2458-5-65-S1.pdf] Acknowledgements This study was supported by a Grant-in-Aid for Scientific Research by the Japan Society for the Promotion of Science (Grant No. 14570326 and 16590497). The authors wish to thank Dr Masahiro Umezaki (Graduate School of Tokyo Medical and Dental University) for technical advice on geographic mapping and Dr Tomoki Nakaya (Ritsumeikan University) for helpful com- ments on statistics. References 1. Health and Welfare Statistics, Association: Kokumin Eiseino Doko. Tokyo: Health and Welfare Statistics Association; 2003. 2. Robine JM, Romieu I, Cambois E: Health life expectancy indicators. Bull World Health Organ 1999, 77:181-185. 3. 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