Measuring radiation fibrosis: The interobserver reliability of two methodsof determining the degree of radiation fibrosis

Purpose: To compare the interobserver reliability of the palpation method w ith the method of measuring tissue compliance with a tissue compliance mete r (TCM) on women who underwent breast-conserving surgery and radiotherapy f or breast cancer. Methods and Materials: Thirty-eight patients and 30 controls were measured with the palpation method by two radiation oncologists and with the TCM by two physiotherapists, Measurements were taken on four locations of the brea sts of all 68 women. Reliability coefficients were computed for both method s. A weighted kappa score was computed for the palpation method and this wa s compared with the intraclass correlation coefficient (ICC) computed for t he TCM method. The conditions for direct comparison of these scores were me t in this study. Results: A weighted kappa of 0.65 was computed for the palpation method and an ICC of 0.91 was computed for the TCM method. These scores differ signif icantly from each other (p < 0.01). Conclusion: The interobserver reliability of the TCM method is superior to that of the palpation method. However, at locations where the TCM is not ap plicable, palpation is a good alternative. (C) 2000 Elsevier Science Inc.