To detect validity and reliability of the Questionnaire of Olfactory Disorders (QOD) compared to other quality-of-life (QoL) questionnaires, to explore its ability to reflect olfaction-related QoL changes, and to investigate age- and gender-related effects of olfactory changes on QOD results.
Prospective clinical study.
One hundred two patients (56 males, 46 females; mean age, 41.15 ± 16.31 years), suffering from chronic rhinosinusitis, whose olfactory function was measured using Sniffin' Sticks test were studied. All patients completed three validated general health-related QoL questionnaires (Short Form-36 Health Survey [SF-36], Beck Depression Inventory [BDI], and Zung anxiety scale), and the olfaction-related QOD.
Internal consistency and test-retest reliability for the QOD was high. Convergent validity assessment showed statistically significant negative correlations of the QOD and the QOD-negative statements (NS) with overall SF-36 score (P < .05 for all groups) and positive correlations of the same scores with BDI and Zung (P < .001). The QOD-positive statements (PS) was positively correlated to SF-36. Discriminative validity demonstrated statistically significant differences of the QOD and QOD-NS scores between all groups of patients (normosmics, hyposmics, anosmics; all pairwise comparisons, P < .001). The QOD-PS score was significantly higher in normosmics and hyposmics compared to anosmics. Patients' age was negatively correlated with the QOD-PS, whereas it was positively correlated with BDI (P < .001) and Zung (P = .007). Females presented significantly higher scores in the QOD, QOD-NS, BDI, and Zung (all P < .001) compared to males.
The QOD proved to be a valid, reliable, and easy-to-use method of assessment of olfaction-related QoL with high specificity and sensitivity. Laryngoscope, 2012