International Journal of Preventive Medicine (Int J Prev Med)2008-78021052019060220672067ENDepartment of Biostatistics, School of Public Health, Sabzevar University of Medical Sciences, SabzevarDepartment of Statistics and Epidemiology, Faculty of Health, Road Traffc Injury Research Center, Tabriz University of Medical Sciences, TabrizDepartment of Biostatistics, School of Public Health, Kermanshah University of Medical Sciences, KermanshahDepartment of Biostatistics, School of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, TehranDepartment of Biostatistics, School of Medicine, Shiraz University of Medical Science, ShirazDepartment of Public Health, Mareagheh University of Medical Science, Maragheh20190602<p><span class="fontstyle0"><strong>Background</strong>: </span><span class="fontstyle2">Gastric cancer (GC) is the frst and the third prevalent cancer among males and females in Iran, respectively. The aim of this study was mainly to identify high‑risk areas of GC by assessing the spatial and temporal pattern of incidence, and second, to explore some risk factors of GC in ecological setting. </span></p><p><span class="fontstyle0"><strong>Methods</strong>: </span><span class="fontstyle2">In this cross‑sectional ecological study we used Bayesian hierarchical space‑time model to measure the relative risk and temporal trends of GC in<br />Iran from 2005 to 2010 based on available data. Data analysis was done by the use of integrated nested Laplace approximation Bayesian approach in R software. </span></p><p><span class="fontstyle0"><strong>Results</strong>: </span><span class="fontstyle2">Overall trend of GC was signifcantly decreasing during the study period. Ardabil, Khorasan Razavi, West Azarbaijan, Zanjan, and Mazandaran provinces had the highest risk of incidence. Overweight and smoking were directly and signifcantly associated with GC risk. </span></p><p><span class="fontstyle0"><strong>Conclusions</strong>: </span><span class="fontstyle2">During the study period, GC has decreased in Iran. Nevertheless, GC risk was generally high in Northern and Northwestern provinces of Iran. Different health policies according to GC risk and trend are required for each province.<br />Improvements in screening and education programs and conducting further epidemiological studies could help to reduce the incidence of GC in high risk provinces.<br /></span></p><p><span class="fontstyle0" style="color: #00652e;"><strong>Keywords</strong>: </span><span class="fontstyle3">Bayesian, disease mapping, gastric cancer, hierarchical space‑time</span></p>http://ijpm.mui.ac.ir/index.php/ijpm/article/view/2067http://ijpm.mui.ac.ir/index.php/ijpm/article/download/2067/717717885