Construction and validation of a machine learning algorithm-based predictive model for difficult colonoscopy insertion

Figure 1  Least absolute shrinkage and selection operator regression variable screening diagram.

Figure 2  Random forest model.

Figure 3 Mean decrease Gini diagram of random forest. BMI: Body mass index; RF: Random forest; SAS: Self-Rating Anxiety Scale.

Figure 4 Receiver operating characteristic curves in training and validation set. A: Receiver operating characteristic (ROC) curves of three models in training set; B: ROC curves of three models in validation set. AUC: Area under the receiver operating characteristic curve; LASSO: Least absolute shrinkage and selection operator; RF: Random forest.

Figure 5 Decision curve analysis curves in training and validation sets. A: Decision curve analysis (DCA) curves of three models in training set; B: DCA curves of three models in validation set. LASSO: Least absolute shrinkage and selection operator; RF: Random forest.

Figure 6 Nomogram prediction model incorporating selected risk factors. SAS: Self-Rating Anxiety Scale.