Development and Validation of the Parosmia Olfactory Dysfunction Outcomes Rating (DisODOR)

Area of Science:

• Otorhinolaryngology
• Quality of Life Research
• Olfactory Dysfunction

Background:

• Dysosmia, including parosmia, significantly impacts patient quality of life.
• Existing measures may not adequately capture the specific functional impairments associated with smell distortion.

Purpose of the Study:

• To develop and validate a novel quality-of-life (QoL) outcome measure for patients with dysosmia, specifically parosmia.
• To create a reliable and sensitive instrument for assessing the impact of smell distortion on daily functioning.

Main Methods:

• A 59-item pilot survey was developed with input from parosmia patients and otolaryngologists.
• Item reduction resulted in the 29-item Parosmia Olfactory Dysfunction Outcomes Rating (DisODOR) scale.
• Validation involved assessing reliability, validity (face, content, convergent, discriminative), and sensitivity to change in cases and controls.

Main Results:

• The DisODOR scale demonstrated good discriminative validity between parosmia cases (n=134) and controls (n=20).
• High test-retest reliability (r=0.942) and internal consistency (Cronbach's α=0.971) were observed.
• The scale showed moderate correlation with SNOT-22 scores and excellent association with severity categories, with a minimal clinically important difference (MCID) of 15.

Conclusions:

• The DisODOR is a valid and reliable QoL instrument for parosmia.
• It accurately measures the functional impact and QoL impairment in parosmia patients.
• The scale's sensitivity to change makes it suitable for clinical trials investigating parosmia treatments.