Development of the reflux finding score for infants and its observer agreement

It is hypothesized that laryngeal edema is caused by laryngopharyngeal reflux (LPR) (ie, gastroesophageal reflux extending into the larynx and pharynx). The validated reflux finding score (RFS) assesses LPR disease in adults. We, therefore, aimed to develop an adapted RFS for infants (RFS-I) and assess its observer agreement. Visibility of laryngeal anatomic landmarks was assessed by determining observer agreement. The RFS-I was developed based on the RFS, the found observer agreement, and expert opinion. An educational tutorial was developed which was presented to 3 pediatric otorhinolaryngologists, 2 otorhinolaryngologists, and 2 gastroenterology fellows. They then scored videos of flexible laryngoscopy procedures of infants who were either diagnosed with or specifically without laryngeal edema. In total, 52 infants were included with a median age of 19.5 (0-70) weeks, with 12 and 40 infants, respectively, for the assessment of the laryngeal anatomic landmarks and the assessment of the RFS-I. Overall interobserver agreement of the RFS-I was moderate (intraclass correlation coefficient = 0.45). Intraobserver agreement ranged from moderate to excellent agreement (intraclass correlation coefficient = 0.50-0.87). A standardized scoring instrument was developed for the diagnosis of LPR disease using flexible laryngoscopy. Using this tool, only moderate interobserver agreement was reached with a highly variable intraobserver agreement. Because a valid scoring system for flexible laryngoscopy is lacking up until now, the RFS-I and flexible laryngoscopy should not be used solely to clinically assess LPR related findings of the larynx, nor to guide treatment