Intra-Observer and Interobserver Consistency in the Diagnosis of Lower Airway Malacia Using Dynamic Flexible Bronchoscopy in Pediatric Patients.

Background: Lower airway malacia (LAM) is characterized by excessive collapsibility of the airway during expiration. Although flexible bronchoscopy is widely employed for diagnosis, it is prone to Interobserver variability and technical limitations. This study aims to evaluate intra- and Interobserver consistency in diagnosing LAM in pediatric patients using dynamic flexible bronchoscopy and to assess the impact of bronchoscope size and observer training on diagnostic agreement.

Methods: Pediatric patients who underwent fiberoptic flexible bronchoscopy for dynamic evaluation of LAM were included in this study. A total of 100 anonymized video recordings (50 with diagnosed with LAM and 50 classified as normal) were randomly selected for review. Six pediatric pulmonology specialists independently evaluated these recordings for the presence of LAM, including tracheomalacia (TM) and bronchomalacia (BM), using standardized diagnostic criteria. Interobserver and intra-observer consistency were assessed through statistical analysis with Cohen's Kappa coefficient.

Results: Intraobserver consistency for diagnosing LAM ranged from substantial to almost perfect (0.675 to 0.857). Interobserver consistency was moderate to substantial (0.583 to 0.689), showing the highest agreement for TM when using the 2.8 mm bronchoscope. Center 1, where evaluations were conducted by a single trainer, demonstrated higher Interobserver consistency (0.606 to 0.689) than Center 2, which involved multiple trainers (0.502 to 0.562). The agreement was notably lower for BM, especially within the intermediate bronchi.

Conclusion: The observed variability in diagnostic consistency highlights the critical need for standardized diagnostic guidelines, which could improve treatment outcomes for pediatric patients with LAM.