Intraobserver and interobserver reliability in laryngopharyngeal sensory discrimination thresholds: A pilot study

Objectives: Laryngopharyngeal sensory discrimination threshold (LPSDT) testing is a method used to detect sensory deficits in patients in whom swallowing disorders are suspected. LPSDTs have been used to stratify patient risk status with regard to aspiration and to guide dietary management. The aim of this pilot study was to evaluate the intraobserver and interobserver reliability of LPSDT testing among a group of examiners with differing levels of testing experience. Methods: Twenty-seven healthy volunteers were enrolled in the study to elicit LPSDTs for intraobserver and interobserver reliability measurements. The examiners represented 3 levels of testing experience: an attending laryngologist, a laryngology fellow, and an otolaryngology resident. With the examiners blinded to test results, each subject was examined twice by one examiner and once by a different examiner in an alternating fashion. Results: Six subjects were unable to tolerate the examinations because of coughing and gagging. Spearman rank correlations revealed strong intraobserver reliability for the experienced endoscopists (ie, attending and fellow) but poor reliability for the novice endoscopist (ie, resident). Poor interobserver reliability regardless of endoscopy experience was found. Eighteen percent of the participants demonstrated LPSDTs of more than 4.0 mm Hg (above normal). Conclusions: 1) Intraobserver reliability was good for experienced endoscopists. 2) Interobserver LPSDT agreement between endoscopists was poor. 3) Eighteen percent of the subjects demonstrated elevated LPSDT thresholds of more than 4 mm Hg.