Re-analysis and generation of Overstay2 model: Difference between revisions
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*For each site's training set and validation set, chi square test for independence between the variable OS (Overstay >= 10days and Overstay < 10d) and each factors listed [[Data definition for contributing factors for the Overstay2 project]] to identify the factors that may affect the overstay individually. | *For each site's training set and validation set, chi square test for independence between the variable OS (Overstay >= 10days and Overstay < 10d) and each factors listed [[Data definition for contributing factors for the Overstay2 project]] to identify the factors that may affect the overstay individually. | ||
*Methodology to find the '''best''' model involves | *Methodology to find the '''best''' model involves | ||
** Basic plan for selecting the variables for the model - | ** Basic plan for selecting the variables for the model - perform logistic model with the OS as the dependent variable and the independent variables beginning with the results from univariable analysis above and then by multivariable analysis using all independent variables (full model) and select via stepwise procedure both forward and backward selection. Examine the importance of each variable included based on the probability result of its coefficient. Those not contributing to the model are eliminated and new model is fitted. The process of deleting, refitting and verifying continues until it appears that all important variables are already included. | ||
** Assess the adequacy of the model both in terms of the individual variables and its overall fit - Estimated coefficients showing p-values of < 0.05 or having clinical relevance with p-values higher or close to 0.05 are included in the model. | |||
{{DJ | | {{DJ | | ||
* the statistical tests that were done to evaluate the model | * the statistical tests that were done to evaluate the model | ||