Reliability and validity of an observer-rated disfigurement scale for head and neck cancer patients

Facial disfigurement is considered to be one of the most distressing aspects of head and neck cancer and its treatment, but it has been the focus of little systematic study. Existing studies have yielded conflicting results about the psychosocial impact of disfigurement. No studies to date have examined disfigurement using a valid and reliable observer-rated measure. The purpose of the current study was to examine the validity (convergent and discriminant) and the inter-rater reliability of a novel nine-point observer-rated disfigurement scale.

The sample consisted of 74 ambulatory head and neck cancer patients more than 6 months post treatment. Ratings of disfigurement were assigned independently by surgical and nonsurgical raters. Validity was assessed by comparing the association between disfigurement ratings and sociodemographic and illness treatment variables. Reliability was assessed by examining the concordance between the surgical and nonsurgical ratings.

Disfigurement ratings were not associated with several sociodemographic variables, supporting the discriminant validity of the scale. Disfigurement was significantly related to a diagnosis of oral cancer, a history of adjunctive radiation, the type of surgical procedure performed, the degree of physical dysfunction, and the presence of postoperative complications. Observer ratings of disfigurement were significantly related to patient ratings of disfigurement. These findings support the convergent validity of the disfigurement scale. Inter-rater reliability of the scale was high (intraclass correlation coefficient =.91).

The study provides preliminary evidence for the validity and inter-rater reliability of a novel nine point observer-rated disfigurement scale that may be useful in evaluating the impact of disfigurement on quality of life in head and neck cancer.