Validity and reliability of the total rating of eye, nasal, and dry-mouth (TREND) score

Objective: To develop and validate the total rating of eye, nasal, and dry-mouth (TREND) score, which is a patient-reported outcome measure of upper aerodigestive tract mucosa dryness. Method: Patients with dry symptoms and findings of mouth, laryngopharynx, nose, and eyes were prospectively recruited between June 2024 to November 2025. Patients and healthy individuals completed TREND score within a 7-day period to assess test-retest reliability. Internal consistency was measured using Cronbach’s α for TREND items and sub- and total scores in patients and controls. For patients with dry vocal fold or reflux-related dry throat, validity was evaluated by comparing the TREND with the reflux symptom score (RSS) and the voice handicap index (VHI). Dry findings were collected. Pre-to posttreatment evolution of TREND was assessed to evaluate the responsiveness to change. Results: A total of 164 consecutive patients with dry mucosa complaints completed evaluations (106 females), alongside 85 controls (44 females). Mean TREND sub-/total scores were significantly higher in patients versus controls, demonstrating adequate discriminant validity. External validity showed moderate-to-strong correlations between TREND and RSS in LPRD patients (rs=0.650;95%CI: 0.535–0.742;p = 0.001) and between TREND and VHI in hoarseness patients (rs=0.437;95%CI: 0.234–0.603;p = 0.001). Internal consistency was high (α = 0.856), with moderate-to-high test-retest reliability. ROC analysis suggested a TREND > 19 as pathological threshold in this population (AUC = 0.837;sensitivity:83.5%,specificity:54.8%; Youden index:0.383). Conclusion: TREND score is a valid and reliable patient-reported outcome questionnaire documenting dry throat, mouth, nose, and eye symptoms in otolaryngology. Future studies are needed to establish psychometric properties of TREND in several other dry disorders.