Assessing The Ceiling Effect Of Physical Function Assessment Tools In Exercise Oncology

PURPOSE: Maintaining and enhancing physical function is essential for the long-term health and quality of life of cancer survivors. However, commonly used physical function assessment tools may be limited by ceiling effects, especially in higher-functioning individuals. Therefore, the purpose of this study was to examine the presence of ceiling effects in the Bellarmine Norton Assessment Tool (BNAT) and the Short Physical Performance Battery (SPPB). METHODS: Individuals previously treated for cancer participated in a supervised 8-week resistance exercise program (2 sessions/week). Physical function was assessed using the BNAT and SPPB scaled scores at baseline and post-intervention. To assess ceiling effects, proportions of baseline scores within minimal detectable change (MDC) thresholds of maximum scores were calculated (BNAT within 3 points of 25; SPPB within 1 point of 12). Changes in scores were analyzed using the Wilcoxon signed-rank test, and Hedges' d effect sizes were calculated to quantify change magnitude. RESULTS: Twenty-seven survivors (5 men, 22 women; mean age = 61 ± 11 years), primarily treated for breast cancer (67%), completed the intervention. At baseline, 13.8% scored within 3 points of the maximum BNAT score, and 34.5% scored within 1 point of the maximum SPPB score. Additionally, 3.7% reached the maximum BNAT score, while 18.5% reached the maximum SPPB score. Post-intervention, significant improvements were observed in both BNAT (Hedges' d = 1.08, p < 0.001) and SPPB (Hedges' d = 0.64, p = 0.003) scores. At post-intervention, 40.7% scored within 3 points of the maximum BNAT score, and 62.9% within 1 point of the maximum SPPB score, with 11.1% achieving the maximum BNAT score and 44.4% reaching the maximum SPPB score. CONCLUSIONS: The exercise program significantly improved physical function as measured by the BNAT and SPPB scaled scores. However, the greater ceiling effect and smaller effect size observed in the SPPB suggests it may be less sensitive for detecting changes in higher-functioning individuals. These findings highlight the importance of selecting appropriate assessment tools for evaluating physical function in cancer survivors. Future studies should use a larger sample to explore the long-term use of these tools and their application across diverse survivor demographics. Supported by: No grant funding