Development and Validation of a Temporal Progression-based Risk Assessment Tool for Respiratory Syncytial Virus...

Respiratory syncytial virus (RSV) causes an estimated 3.2 million infant hospitalizations worldwide annually, with 99% of RSV-associated deaths occurring in developing countries. Although laboratory confirmation remains the standard for diagnosis, resource limitations and the need for prompt infection control measures highlight the importance of reliable symptom-based assessment tools.

In this retrospective cohort study (2009-2015), we analyzed symptom characteristics and progression patterns in infants 12 months of age or younger who underwent RSV rapid antigen testing at a tertiary care center, regardless of subsequent hospitalization status. Through structured electronic questionnaires and chronologically divided development and validation cohorts, a predictive model incorporating symptom features and their sequence patterns was developed using multivariable logistic regression analysis. The model was then transformed into a weighted risk score system, for clinical application.

Among 1650 eligible infants, RSV was detected in 328 patients (19.9%). The model incorporated productive cough, biphasic wheezing and cough-wheezing progression sequences as key predictors. The model demonstrated moderate discriminative ability in the development cohort [area under the receiver operating characteristic curve (AUROC), 0.746; 95% confidence interval (CI): 0.715-0.777] and maintained its performance in the validation cohort (AUROC, 0.712; 95% CI: 0.626-0.798). Risk stratification effectively identified RSV-positive cases, with RSV probability rates of 5.6%, 7.2%, 22.6% and 41.2% across baseline, moderate, elevated and high-risk groups, respectively.

This symptom-based index provides reliable risk stratification for RSV infection through systematic assessment of respiratory symptoms, offering a potential screening method for various clinical settings.