The Validity and Reliability of Reflux Symptom(RSI) Index and Reflux Finding Score(RFS)

역류증상지수와 역류소견점수의 타당성과 신뢰도

Laryngopharyngeal reflux (LPR) is the retrograde movement of gastric contents into the larynx, pharynx, and upper aero-digestive tract. LPR differs from gastroesophageal reflux in that it is often not associated with heartburn and regurgitation symptoms. Otolaryngological manifestations of acid reflux include a wide range of pharyngeal and laryngeal symptoms. Belafsky et al. developed a useful self-administered tool, the reflux symptom index (RSI), for assessing the degree of LPR symptoms. Patients are asked to use a 0 to 5 point scale to grade the following symptoms: 1) hoarseness or voice problems; 2) throat clearing; 3) excess throat mucus or postnasal drip ; 4) difficulty swallowing; 5) coughing after eating or lying down; 6) breathing difficulties ; 7) troublesome or annoying cough; 8) sensation of something sticking or a lump in the throat; 9) heartburn, chest pain, indigestion or stomach acid coming up. A RSI score greater than 13 is considered abnormal. As there is no validated instrument to document the physical findings and severity of LPR, Belafsky et al. developed an eight-item clinical severity scale for judging laryngoscopic finding, the reflux finding score (RFS). They rated eight LPR-associated findings on a scale from 0 to 4 : subglottic edema, ventricular obliteration, erythema/hyperemia, vocal-fold edema, diffuse laryngeal edema, posterior commissure hypertrophy, granuloma/granulation tissue, and thick endolaryngeal mucus. A RFS score of greater than 7 was found to suggest LPR-associated laryngitis. Although both indices (RSI and RFS) are widely used, there is some controversy about their validity (sensitivity and specificity) and reliability (intra-rater and inter-rater) in LPR diagnosis and treatment. We discuss the validity and reliability of RSI and RFS with literature review.