Assessment of the Validity of the Sinonasal Outcomes Test-22 in Pituitary Surgery: A Multicenter Prospective Trial.

Abstract

Sinonasal Outcomes Test-22 (SNOT-22) is used widely as a patient-reported sinonasal quality-of-life (QOL) instrument for endoscopic endonasal pituitary surgery. However, it has never been validated in this population. This study explores the psychometric validity of SNOT-22 to determine if it is a valid scale in patients undergoing endoscopic pituitary surgery. Multicenter prospective trial. Adult patients (n=113) with pituitary tumors undergoing endoscopic surgery were enrolled in a multicenter study. Patient-reported QOL was assessed using SNOT-22 and the Anterior Skull Base Nasal Inventory-12. Face validity, internal consistency, responsiveness to clinical change, test-retest reliability, and concurrent validity were determined using standard statistical methods. Internal consistency using Cronbach's alpha at baseline and 2 weeks postoperatively were 0.911 and 0.922, indicating SNOT-22 performed well as a single construct. Mean QOL scores were significantly worse at 2 weeks than baseline (16.4 ± 15.1 vs. 23.1 ± 16.4, P < .001), indicating the scale is responsive to clinical change. However, only 11/22 items demonstrated significant changes in mean scores at 2 weeks. Correlation between scores at 2 and 3 weeks was high, suggesting good test-retest reliability, r(107)=0.75, P < .001. Factor analysis suggests the five-factor solution proposed for the SNOT-22 in rhinosinusitis patients is not valid in pituitary surgery patients. The SNOT-22 is a valid QOL instrument in patients undergoing endoscopic pituitary surgery. However, because it includes 22 items, can be applied only as a single construct, 50% of the items do not demonstrate changes after surgery, and is not as sensitive to change as other scales, shorter instruments developed specifically for this patient population may be preferable. 2 Laryngoscope, 131:E2757-E2763, 2021.