Application of explainable machine learning in early diagnosis models for risk prediction of severe Mycoplasma pneumoniae pneumonia in children
摘要
Mycoplasma pneumoniae (MP) is a major pathogen of community-acquired pneumonia (CAP) in children. Severe Mycoplasma pneumoniae pneumonia (SMPP) poses a significant threat to pediatric health. Current diagnostic approaches rely primarily on imaging and clinical signs and lack objective and quantitative tools for early risk prediction. This study aimed to develop an explainable machine learning (ML) model for the early prediction of SMPP risk in children.
MethodsA retrospective analysis was conducted on data from 507 pediatric inpatients with M. pneumoniae pneumonia (MPP) admitted to the Affiliated Hospital of Yan’an University between January 2023 and December 2024. Clinical characteristics were compared between the MPP and SMPP groups. Key predictors were identified using the Mann–Whitney U test, chi-square test, Pearson correlation analysis, and least absolute shrinkage and selection operator (LASSO) regression. Seven ML models were constructed. Hyperparameters were optimized through fivefold cross-validation and grid search. Model performance was evaluated using the following metrics: accuracy, precision, recall, F1 score, and the area under the curve (AUC). Model interpretability was analyzed using the SHapley Additive exPlanations (SHAP) method.
ResultsFollowing feature selection, 21 variables were retained. Seven ML models were constructed and evaluated for their predictive efficacy. Among them, the Categorical Boosting (CatBoost) model demonstrated optimal performance, achieving an AUC of 0.882 and an accuracy of 0.850. Decision curve analysis (DCA) was employed to assess the clinical utility of these models. Within the threshold probability range of 0.3 to 0.8 in the test set, the CatBoost model exhibited a superior net benefit compared to the other ML models. In the external validation, the model achieved an AUC of 0.769. Furthermore, the SHAP method was applied to interpret the CatBoost model. The SHAP analysis identified the following five key features as contributing most to the model’s predictions, listed in order: peak temperature, duration of fever, lactate dehydrogenase (LDH), platelet count (PLT), and D-dimer.
ConclusionsThis study developed an explainable machine learning model based on the CatBoost algorithm, providing a potential quantitative tool for the early risk warning of SMPP in children. The model demonstrated favorable discriminatory performance and a certain degree of generalizability within the retrospective cohort. Furthermore, interpretability analysis revealed key clinical risk factors, including peak temperature, duration of fever, LDH, PLT, and D-dimer, among which peak temperature and fever duration contributed the most to the predictions. These findings provide a transparent and quantitative basis for early clinical identification and decision-making.