Quality of Life After Endoscopic Skull Base Surgery: Validation and Reliability of the Italian Version of the Sino-Nasal Outcome Test for Neurosurgery (SNOT-NC)

Abstract

Expanded endonasal approaches (EEA) have become the main approach to the anterior skull base. A specific questionnaire, the Sino-Nasal Outcome Test for Neurosurgery (SNOT-NC), was developed in German to assess quality of life after EEA. The aim of this study was the cross-cultural adaptation and validation of the Italian version of SNOT-NC. Three hundred patients who underwent EEA for anterior skull base diseases were included in the study. An Italian version of SNOT-NC was cross-culturally adapted. Internal consistency, test-retest reliability, construct, and clinical and group validity were analyzed. The Short-Form 36 questionnaire was used for construct validity analysis. The Cronbach α coefficient was 0.862. Only 1 subscale (olfactory disturbance) showed an insufficient internal consistency. The test-retest reliability was excellent (intraclass correlation coefficient between 0.934 and 0.997). The good correlation between SNOT-NC and Short-Form 36 scores (P < 0.05) showed the construct validity of the questionnaire. SNOT-NC was able to distinguish between patients with more or fewer nasal symptoms (P < 0.05). Patients who underwenta transtuberculum/transplanum approach had greater olfactory disturbances compared with other approaches (P < 0.05). The Italian version of SNOT-NC showed good internal consistency, test-retest reliability, construct, and clinical and group validity, as well as original version. It can be considered a good instrument to evaluate the impact of endoscopic EEA to the anterior skull base.