The reliability and validity of Dokuz Eylul University Meniere's Disability Scale in assessment of patients with Meniere's disease

Objective: Ménière's Disease is a chronic, non–life-threatening inner-ear disease, with attacks of disabling vertigo, progressive hearing loss, and tinnitus as major symptoms. All three symptoms, separately or in combination, cause great distress and have a considerable impact on the quality of life of patients. The first aim of this study was to analyze the psychometric properties of Dokuz Eylul University Meniere's Disability Scale developed originally. On the other hand the second objective of this study was to analyze the relationship between clinical, audiological and vestibular findings and the scores of the scale of patients with Meniere's disease. Method: ENT examination, clinical history recordings and audiovestibular tests were performed to 93 patients with definite Meniere's disease. Dokuz Eylul University Meniere's Disability Scale and Turkish version of the Dizziness Handicap Inventory were administered. Cronbach's alpha coefficient, p values of Tukey's additivity and Hotelling's chi-square tests, intra-class correlations coefficients, item-total correlations coefficients, Cronbach's if item deleted values were calculated. And exploratory factor analyses by Varimax rotation with Kaiser normalization and confirmatory factor analyses of Dokuz Eylul University Meniere's Disability Scale by goodness of fit tests were performed. Results: 45 (48.4%) of patients were male, 48 (51.6%) were female and the mean age was 48.9 ± 12.1 years. The mean duration of Meniere's disease was 5.6 years. Means of 0.5-2 kHz and 0.5-3 kHz hearing thresholds were 46.8±21.4 dB HL and 47.4±22.3 dBHL respectively at the pathological side of unilateral Meniere's disease patients (n:87). In bilateral cases (n:6) these values were 58±14.4 dBHL and 54.8±19 dBHL respectively at the right side, 46±14.7 dBHL and 49.5±21.4 dB HL respectively at the left side. Vestibular function test findings including eyes closed tandem gait, sharpened Romberg and Unterberger tests were encountered abnormal over 50% of the patients. In videonystagmography, spontaneous nystagmus was detected 16% and bi-thermal caloric test showed 48% canal paresis of the involved ear of the cases. Patient age was found to be significantly positively correlated with audiological findings and the attack severity. There was also a strong positive correlation between the caloric responses and audiological findings of involved ears. Cronbach's alpha was 0.92, intra-class correlation value was significant (p <0.001). Both Tukey's and Hotelling's tests showed significancy (p<0.001). Results of the goodness of fit statistics showed that the expression levels of the items to the scale was high, and the relationships of item-scale were sufficient. Conclusion: As a result of this study, Dokuz Eylul University Meniere's Disability Scale is a valid and reliable scale.