Development of a cancer-specific anterior skull base quality-of-life questionnaire

Abstract

Object. The goal of this study was to develop a disease-specific, multidimensional quality of life (QOL) assessment instrument for patients undergoing surgical extirpation of anterior skull base tumors. Methods. This investigation included 35 patients who had been surgically treated for more than 3 months before the study was begun. Relevant QOL questions were generated from a review of the literature and interviews with health professionals, patients, and their caregivers. The initial multidimensional, 80-item questionnaire was reduced to a 35-item questionnaire by using standard psychometric criteria. Six relevant domains were identified using factor analysis: performance, physical function, vitality, pain, specific symptoms, and influence on emotions. The internal consistency of the instrument had a correlation coefficient of 0.8 and a reliability coefficient (test—retest reliability) of 0.9. The validity of the construct was assessed by testing whether the clinical variable of the patient influenced his QOL domain score as hypothesized. Patients older than 60 years of age had significantly poorer scores in the domains of performance and physical function than younger patients. Patients with malignant tumors had significantly poorer scores in the domains of specific symptoms, influence on emotions, physical function, and performance compared with patients with benign tumors. Radiotherapy was associated with poorer scores in the domains of specific symptoms and influence on emotions. Comorbidity was associated with poor physical function scores. Using the final questionnaire, we prospectively evaluated the QOL of 12 additional patients before they underwent surgery and again between 5 and 6 months postoperatively to test the utility and validity of the instrument further. Again, significantly poorer QOL scores were recorded for patients with malignancy. Conclusions. The proposed questionnaire appears to be sufficiently reliable and valid in estimating a patient's QOL after extirpation of anterior skull base tumors. The instrument can be used in face-to-face interviews and via electronic or regular mail.