Translation and validation of the Korean Version of the Reflux Symptom Score

To assess the validity and reliability of the Korean version of the reflux symptom score (K-RSS).The English version of the RSS was translated into Korean and completed by 77 people (44 and 33 people in the patient group and control group, respectively). They completed the K-RSS (K-RSS-1) and reflux symptom index (RSI) questionnaires and answered questions about age, sex, underlying disease, smoking history, and alcohol and coffee consumption. They completed the K-RSS once more (K-RSS-2) after 1 - 2 weeks. Internal consistency was evaluated using Cronbach's α and test-retest reliability using the intraclass correlation coefficient (ICC). External validity was evaluated using the Spearman rank test between the RSI and K-RSS. The Mann-Whitney U test was used to assess internal validity by comparing the K-RSS-1 scores between the patient and control groups.The most common symptoms were globus sensation, throat clearing, and throat pain. The K-RSS reported high internal consistency (α = 0.894). The ICC for the total score was 0.883, indicating excellent test-retest reliability. According to the Spearman analysis, there was a significant correlation between the total score of the K-RSS and that of the RSI (rs = 0.902; P < 0.001), demonstrating strong external validity. Furthermore, the patient group showed significantly higher values than the control group in all K-RSS scores, suggesting high internal validity.The K-RSS is a patient-reported outcome questionnaire with excellent criterion-referenced validity and ideal reliability.