Background and objectives: Post-COVID-19 olfactory dysfunction persists in many patients and significantly affects quality of life. The primary objective was to evaluate olfactory function using psychophysical tests (BAST-24) and quality-of-life questionnaires. Secondary objectives included analysing correlations between questionnaires and the relationship between subjective and psychophysical measures.
Materials and methods: A prospective study was conducted including 86 adults with olfactory dysfunction ≥ 6 months after SARS-CoV-2 infection. Clinical and demographic data and scores from the Visual Analog Scale for smell (VAS-smell) and the SNOT-22, svQOD-NS, and QVOLF questionnaires were collected. Olfactory function was assessed using the BAST-24 (detection, identification, and olfactory memory). Descriptive statistics, Spearman's correlation coefficient, and the Mann-Whitney U test were used (p < 0.05).
Results: Mean age was 49 years (SD = 14); 76.7% were women. According to the VAS, 90.7% had hyposmia and 8.1% anosmia. Mean scores (SD) were: VAS 6 (2), SNOT-22 26 (20), svQOD-NS 4 (4), and QVOLF 127 (50), suggesting a moderate impact on quality of life. BAST-24 scores: detection 91% (22), identification 52% (25), and memory 35% (20). QVOLF and svQOD-NS showed a strong correlation (ρ = 0.797; p < 0.001), while SNOT-22 correlated moderately with both. No significant correlations were found between any questionnaire and BAST-24.
Conclusions: QVOLF and svQOD-NS questionnaires are more sensitive than SNOT-22 for assessing olfactory dysfunction. The lack of correlation with psychophysical tests highlights the need to combine both approaches fora comprehensive evaluation.
Introduction: To perform the cross-cultural adaptation into Spanish and the psychometric validation of the Nasal Polyposis Quality of Life Questionnaire (NPQ) for use in patients with chronic rhinosinusitis with nasal polyps (CRSwNP).
Methods: A total of 140 adult patients diagnosed with CRSwNP were included. The original NPQ was adapted from Italian into Spanish following established international guidelines. Construct validity was assessed through exploratory factor analysis (EFA) with principal components. Internal consistency was analyzed using Cronbach's alpha coefficient. Test-retest reliability was determined by the intraclass correlation coefficient (ICC). Concurrent validity was examined using Pearson correlations with the SNOT-22 and NOSE-E questionnaires. Discriminant validity was analyzed using ROC curves.
Results: EFA revealed a five-factor structure explaining 67% of the total variance. The Spanish NPQ showed excellent internal consistency (Cronbach's α = 0.917) and high test-retest reliability (ICC = 0.991; 95% CI: 0.983-0.996). The standard error of measurement (SEM) was 2 points, and the minimal detectable change (MDC95) was 5 points. Strong correlations were observed with the NOSE-E (r = 0.802) and SNOT-22 (r = 0.870). The NPQ total score demonstrated high discriminative ability for severe symptoms (AUC = 0.947), with a cutoff point >41 providing 88.9% sensitivity and 93.3% specificity.
Conclusions: The Spanish version of the NPQ is a valid, reliable, and clinically useful instrument for assessing symptom burden in patients with CRSwNP. Its multidimensional structure allows capturing the specific impact of this phenotype and supports its use in both clinical practice and research.

