Machine learning approaches for tuberculosis prevalence and risk factor association among high-risk groups in Kigali...

Tuberculosis (TB) remains a major global health challenge, disproportionately affecting vulnerable populations in resource-limited settings. In Rwanda, the burden is high among high-risk groups including prisoners, mining workers, people living with HIV, and healthcare workers. Despite well-established national surveillance infrastructure, published evidence on applying machine learning (ML) to routinely collected electronic medical records (EMR) for identifying factors associated with TB in these populations remains limited. This study develops and compares multiple ML models to identify factors associated with TB among high-risk groups using national surveillance data from Kigali health facilities, while emphasizing careful feature engineering to avoid information leakage.

We conducted a retrospective, cross-sectional analysis of 2,254 high-risk patient EMR from Rwanda Biomedical Center (RBC) surveillance systems, with TB status defined by GeneXpert results. Rigorous data cleaning and preprocessing were performed, including exclusion of records with indeterminate outcomes, removal of diagnostic and operational variables that could introduce information leakage, imputation of missing values, normalization of numerical features, and one-hot encoding of categorical variables. Multiple supervised ML models were developed and evaluated using a stratified train-test split, including logistic regression (LR), balanced random forest (BRF), gradient boosting methods (XGBoost, LightGBM, and GBM), support vector machines (SVM) with a radial basis function kernel, and an EasyEnsemble classifier. Model performance was assessed using accuracy, precision, recall, F1-score, and area under the receiver operating characteristic (ROC) curve (AUC).

After excluding indeterminate GeneXpert outcomes, 358 cases were retained for evaluation. Ensemble-based models showed consistently strong and stable performance, with BRF achieving the highest discrimination (AUC = 0.86), while GBM, SVM, and EasyEnsemble classifiers showed comparable performance across accuracy, precision, recall, and F1-score. Feature-importance analysis identified clinically meaningful factors, associated with TB, including site of disease, age, TB-related body mass index, HIV status, and diabetes status, indicating that the models relied on plausible biological and demographic risk factors rather than diagnostic artifacts.

This first application of EMR-driven ML for identifying TB risk factor associations in Rwanda shows that ensemble models, combined with rigorous leakage control, achieve promising performance among high-risk populations. These tools could support national TB surveillance and screening to enhance early detection and resource allocation.