Examining The Test-Retest Reliability Of The Bellarmine Norton Assessment Tool In Adult Cancer Survivors

Cancer treatments are accompanied by reductions in physical function that increase the risk of falls, fractures, and mortality. Consequently, monitoring changes in physical function is an important part of supportive care in oncology. Critically, for assessments to be easily implemented in clinical oncology as part of standard care, they need to be inexpensive, quick to implement, and use minimal equipment. The Bellarmine Norton Assessment Tool (BNAT) is an assessment developed to test physical function objectively in older adults and clinical populations. However, the psychometric properties of the BNAT have not been evaluated in cancer. PURPOSE: To assess the validity, reliability, and standard error of measurement of BNAT scores in individuals with cancer. METHODS: Adult cancer survivors completed a BNAT physical function battery, which included a self-reported physical activity question, 30-second sit-to-stand, timed arm-curl, and timed up-and-go tests. The BNAT was performed twice with 48 hours between tests. Each test produces a raw score, which combine total BNAT ranging from 1-25 (higher scores indicate higher functioning). Test-retest reliability was examined using intraclass correlation coefficient (ICC). The measurement error was evaluated with standard error of measurement (SEM) and minimal detectable change (MDC). RESULTS: Sample was twenty adult cancer survivors (n = 20, age 65.35 ± 9.56 y, height 64.75 ± 3.45 in., weight 176.05 ± 33.98 lbs.). The majority of the sample (90%) was female breast cancer and 45% were non-Hispanic White, 45% were Black, 5% were Asian and 5% identified as “Other”. The reliability of the BNAT (intraclass correlation coefficient [ICC2,1] =0.87) was strong (95% confidence interval 0.71-0.95). The standardized measurement of error (SEM) was 0.98, 4.38% of average BNAT score totals, minimal detectable change (MDC) was 2.72. Low SEM and MDC measurements indicated the BNAT had satisfactory reproducibility. CONCLUSIONS: The BNAT physical function test battery demonstrated strong reliability, supporting its use as an assessment of objective physical function testing in clinical oncology settings. The MDC value obtained can provide clinicians with further context when evaluating changes on the total BNAT score in follow-up assessments.