Iranian Journal of

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Background & Objectives: In recent years, different decision support systems (DSS) have been used to predict and diagnose diseases. The purpose of this paper was to compare some DSSs and to evaluate their accuracy in predicting diabetes. 

Methods: In this research, determination and optimization of the weights of the neural network were undertaken using genetic algorithm and Levenberg-Marquardt (GALM). Traditional and K-Fold Cross Validation were used to verify the models. Finally, the proposed model (i.e. GALM) was compared using logistic regression and genetic algorithm based on area under curve (AUC), and Confusion Matrix.

Results: After evaluating the results, the model based on the GALM algorithm showed better sensitivity and specificity in comparison with models based on the logistic regression (LR) and genetic algorithm (GA). Furthermore, among other models, the proposed model had a high sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and a small negative likelihood.

Conclusion: The results showed that the GALM model with a sensitivity, specificity, PPV, NPV, and AUC of 98.7, 90.01, 91.8, 98.3 and 0.979 respectively was an appropriate model for predicting diabetes in comparison with models of GA and LR.

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Background and Objectives: Breast cancer is the most common cancer in Iran. It can be prevented by rapid diagnosis of the disease. Thus, it is necessary to determine the causal relationships between variables related to breast cancer. Bayesian network is a data mining tool that shows the causal relationship between different variables. In this paper, a Bayesian network was applied to find causal relationships between breast cancer variables using a genetic algorithm in a graphical model. 
 
Methods: in this applied study, data were collected from 900 breast cancer patients in Kerman Province from 1999 to 2008. For data analysis, we used a probabilistic graphical model representing the causal relationship between variables.
 
Results: The results showed that surgery was the most important treatment for breast cancer. Based on the conditional and marginal probabilities, the women who underwent surgery had higher hopes of living longer. Moreover, 81% of the patients who did not undergo surgery only received chemotherapy or radiotherapy were less likely to have long lives.
 
Conclusion: People aged 40-65 years are more likely to have breast cancer. Moreover, the variables of age, surgery, chemotherapy, and radiotherapy had a direct effect on the status of the patients and there were direct edges from these variables to the status of the patients.