Objectives: To perform a factor analysis using the University of Washington Quality of Life Questionnaire version 4 (UW-QOLv4) to establish subscales; to report their normative values and variations for patients by age, sex, extent of disease, and time from treatment; and to estimate clinical effect sizes and potential for use in comparative treatment studies.
Design: Retrospective cohort.
Setting: Regional Maxillofacial Unit, University Hospital Aintree, Liverpool, England.
Patients: Patients with primary oral and oropharyngeal cancer treated by surgery with or without adjuvant radiotherapy since 1992. A database accumulating since 1995 contains more than 2600 UW-QOLs completed by these patients. A data set of 372 patients without cancer attending 10 general dental practices provided normative data.
Main outcome measures: UW-QOLv4.
Results: Factor analysis indicated a 2-factor solution: (1) physical function, involving chewing, swallowing, speech, taste, saliva, and appearance, and (2) social-emotional function, involving anxiety, mood, pain, activity, recreation, and shoulder function. The best scores were for those with less advanced oral cancer tumors not requiring free-flap surgery or adjuvant radiotherapy. Older patients reported better scores, but associations were weak, and no sex differences were found. Significant differences were seen for T category, site, free-flap surgery, and adjuvant radiotherapy (P < .001). Preoperative scores were close to normative values. Patients regain social-emotional deficits by 1 year after surgery but continue with significant deficits in physical function. Comparative studies using these UW-QOL subscales as outcome measures should recruit at least 80 patients per treatment arm to detect moderately sized treatment effects.
Conclusion: With the UW-QOLv4, it is appropriate to analyze and report outcomes using the 2 subscales of physical and social-emotional function.