Determination of the Factors Affecting the Survival Rate of Patients with Lung Cancer Using Bayesian Model; Historical Cohort

Introduction: Gastric cancer; Case-Control; Conditional logistic regression; Bayesian; Matching.Gastric cancer is one of the most common and deadly cancers in Iran. Gastric cancer is highly dependent on nutritional factors and geographical location. Therefore, the aim of this study was to evaluate the effect of nutritional factors on gastric cancer in Hamadan-Iran. Methods: This study was performed as a matched case-control study that each case had two controls that matched with cases in age (±5 years) and gender at Diagnostic and Treatment Center of Mahdieh in Hamedan, Iran. First and second control groups contain persons with and without family history of cancer, respectively. Information of nutritional, epidemiological and confounding variables were collected for 100 cases and 200 controls. Controls from hospital samples, friends and acquaintances of the case group were selected. Data were collected using a researcher-made questionnaire. Data were analyzed using conditional logistic regression by Bayesian method. Results: Findings showed that, compared with individuals in the case group with the family history group with factors hot food (OR=2.35, 0.95%CrI=(1.82,5.19)), black tea (OR=1.60, 0.95%CrI (1.44,1.72)) cigarettes (OR=2.13, 0.95%CrI=(1.68,2.96)), red meat (OR=4.28, 0.95%CrI=(3.11,8.37)), residence (OR=3.15, 0.95%CrI= (1.62,5.65)), fruit (OR=0.75, 0.95% CrI=(0.63,0.83)) and vegetables (OR=0.76, 0.95%CrI=(0.59,0.85)) there was a strong statistical correlation. The results were also valid for the second control group. Conclusion: The study showed that many controllable nutritional factors in Hamadan affect the incidence of gastric cancer. It is recommended that policymakers and managers inform the public about the risk factors and prevention of gastric cancer through the publication of brochures, television and newspapers.