Prospective Multicenter Validation of Patient-Reported Nasal Quality-of-Life Tool for Endonasal Skull Base Surgery: The Anterior Skull Base Nasal Inventory-12

Introduction: Patient-reported quality-of-life (QOL) endpoints are becoming increasingly important healthcare metrics. Nasal trauma is one primary source of postoperative morbidity in endonasal skull base surgery. Current nasal morbidity scales have shortcomings, which may limit their applicability for this population. In this study, we describe the development and validation of a site-specific nasal morbidity instrument to assess patient-reported rhinological outcomes following endonasal skull base surgery.

Methods: Eligible patients included those with planned endonasal surgery for sellar pathology using the transsphenoidal corridor identified in outpatient neurosurgical clinics of three skull base centers from October 2011 to July 2012. An initial 23-question survey, consisting of questions about common postoperative nasal complaints, was developed based on information from subject matter experts, a review of the literature, and results of a previous validation study. Symptom severity and importance were ranked by patients. Exploratory factor analysis, change scores, and importance rank were examined to define the final instrument, consisting of 12 items (ASK Nasal-12). Psychometric validation of the final instrument was performed using standard statistical techniques.

Results: The study included 104 patients. All patients completed the preoperative survey, and 100 patients (96%) completed the survey at 2-4 weeks after surgery. Internal consistency of the final instrument was 0.88. Concurrent validity measures demonstrated a strong correlation between overall nasal functioning and total scores (P < 0.000). Test-retest reliability measures demonstrated a significant intra-class correlation between responses (P < 0.000). Effect size, as calculated by standardized response mean, suggested a large effect (0.84). Discriminant validity calculations demonstrated that the instrument was able to discriminate between preoperative and postoperative patients (P < 0.000).

Conclusions: This prospective multicenter study demonstrates that the ASK Nasal-12 is a validated, site-specific, unidimensional rhinological outcomes tool that is sensitive to clinical change. It can be used in conjunction with multidimensional QOL instruments to assess patient-reported nasal perceptions in endonasal skull base surgery.