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

OBJECTIVES

To assess the validity and reliability of the Korean version of the reflux symptom score (K-RSS).

MATERIALS AND METHODS

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.

RESULTS

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.

CONCLUSION

The K-RSS is a patient-reported outcome questionnaire with excellent criterion-referenced validity and ideal reliability.

Translation and Validation of the Arabic Version of the Reflux Symptom Score, Short Version 12 (RSS-12)

BACKGROUND

The Reflux Symptom Score (RSS) is a patient-related outcomes measure (PROM) that was developed to diagnose Laryngopharyngeal reflux (LPR), by assessing the severity and frequency of specific symptoms and their respective impact on quality of life (QoL).

OBJECTIVE

To develop the Arabic version of RSS-12 (Ar-RSS-12), and to assess its validity and reliability.

METHOD

The RSS-12 was translated from French into Arabic using the forward-backward translation method, and the translated version underwent transcultural validation. A case-control study was conducted at the otolaryngology clinics of a referral hospital, during the period November to December 2022. It included 61 patients with LPR-related symptoms and a Reflux Symptom Index (RSI) score >13, and 61 control without LPR-related symptoms and negative RSI scores ≤13. The internal consistency, internal and external validity, and Test-Retest reliability of Ar-RSS-12 were analyzed.

RESULT

Patients had significantly higher scores than controls in all 12 items and total Ar-RSS and QoL impact scores, with high Z score values. Item scores showed variable correlation levels with total Ar-RSS score, with ear-nose-throat items showing the strongest correlation (Spearman's rho 0.592-0.866). The QoL scores were more strongly correlated to the symptoms' severity than frequency. The internal consistency was high, with Cronbach's alpha = 0.878. Regarding external validity, correlations with RSI score showed high Spearman's rho values for total Ar-RSS (0.905) and QoL total score (0.903). No statistically significant difference was observed between Test and Retest results in any of the 12 items' score or the total score and QoL, indicating the reproducibility of the test.

CONCLUSION

The Ar-RSS is a valid and reproducible tool for the screening, assessment, and monitoring of LPR in Arabic speaking patients. The inclusion of symptoms severity and frequency, as well as their individual effects on patient's QoL, support the superior clinical applications of RSS compared to other existing PROMs.