Reliability and concurrent validity of the Courage Kenny-Fibrosis Grading Scale for breast or head and neck cancer-related fibrosis

Objective Fibrosis can develop after surgical or radiation treatments for cancer and is often seen in rehabilitation settings, yet few measures exist for standardized assessment. The aims of this study are to describe the validity and reliability of a new measure for cancer treatment-related fibrosis in survivors of breast or head/neck cancer. Design Face validity of the Courage Kenny-Fibrosis Grading Scale was established using an iterative survey process. Reliability and concurrent validity were assessed using repeated measures by blinded raters and concurrent assessment with the Common Terminology Criteria for Adverse Events, Late Effects Normal Tissue-Subjective, Objective, Management, Analytic scales, and adheremeter rating of skin mobility. Setting Outpatient rehabilitation clinic. Participants Questionnaires were completed by 43 clinicians and researchers in the first round of face validation and 21 in the second. For reliability and concurrent validity, 41 cancer survivors, including 26 post-breast cancer and 15 post-head/neck cancer, were assessed by four physical therapists. Results Adequate face validity of the final version was established using responses from 21 clinicians. Inter-rater and intra-rater reliability of the final scale was adequate at ICC = 0.810 and 0.941, respectively. Associations between the Fibrosis Grading Scale and the Common Terminology Criteria for Adverse Events and Late Effects Normal Tissue scales were moderately significant (r S = 0.290–0.574, p < 0.05), indicating concurrent validity. Conclusion After development of the Fibrosis Grading Scale using an iterative survey process, sufficient reliability and validity was established to use as an assessment in breast and head/neck cancer survivors.