Development, Factor Structure, and Preliminary Psychometric Evaluation of the Rhinitis Medicamentosa Questionnaire (RMQ) Among Topical Nasal Decongestant Users.

BACKGROUND: Rhinitis medicamentosa (RM) is associated with prolonged topical nasal decongestant (TND) use and may involve dependency-like behavioral patterns extending beyond nasal obstruction alone. Existing sinonasal patient-reported outcome measures do not specifically assess these behavioral features. This study aimed to develop the Rhinitis Medicamentosa Questionnaire (RMQ) and perform a preliminary psychometric evaluation in individuals reporting TND use. METHODS: Instrument development followed Waltz's four-stage framework and was informed by Griffiths' addiction model and DSM-5-TR substance use disorder criteria. An initial 50-item pool underwent face and content evaluation involving patients and a multidisciplinary expert panel, resulting in a 37-item version. A total of 390 Hungarian adults reporting TND use within the previous 12 months completed the online questionnaire. Exploratory factor analysis (EFA; n = 210) and confirmatory factor analysis (CFA; n = 180) were performed on non-overlapping subsamples. Internal consistency, preliminary test-retest reliability, and score distribution were assessed. RESULTS: The final RMQ consisted of 16 items across four factors: Overuse, Salience, Tolerance, and Withdrawal. CFA demonstrated good model fit (CFI = 0.975, TLI = 0.970, RMSEA = 0.055). Internal consistency was high across all subscales (Cronbach's α = 0.872-0.944), and preliminary test-retest reliability was favorable (ICC = 0.92). Higher RMQ scores were associated with more frequent and prolonged self-reported TND use. An exploratory sample-derived threshold was identified for higher dependency-related burden within the study population. CONCLUSION: The RMQ is a newly developed multidimensional questionnaire designed to assess dependency-related behavioral patterns associated with prolonged TND use. This preliminary study supports its internal structure, reliability, and interpretability. Further validation in clinically confirmed RM populations and international settings is required.