What is the best method to determine excessive arm volume in patients with breast cancer-related lymphoedema in clinical practice? Reliability, time efficiency and clinical feasibility of five different methods

Objective: To investigate the reliability, time efficiency and clinical feasibility of five commonly used methods for assessing excessive arm volume in patients with breast cancer-related lymphoedema (BCRL). Design: Cross-sectional study. Setting: University Hospitals Leuven, Belgium. Subjects: 30 participants with unilateral BCRL. Methods: Excessive arm volume was determined by five different methods: traditional volumetry with overflow, volumetry without overflow, inverse volumetry, optoelectronic volumetry and calculated volume based on circumference measurements. To investigate intra- and inter-rater reliability, measurements were performed twice by the same assessor and once by a different assessor. Intraclass correlation coefficients (ICCs), standard errors of the measurement (SEMs) and systematic changes between the means were calculated. To determine time efficiency, the mean setup time, execution time and total time were examined for each method. Furthermore, 12 limitations regarding clinical feasibility were listed and scored for each method. Finally, an overall ranking score was determined between the methods. Results: Mean age was 65 (+/- 8) years and mean body mass index was 28 (+/- 4) kg/m(2). Intra- and inter-rater reliability ranged between strong and very strong. Calculated arm volume based on circumferences (mean excessive arm volume: assessor A: 477 (+/- 367) mL; assessor B: 470 (+/- 367) mL; assessor A (second time): 493 (+/- 362) mL) showed the highest intra- and inter-rater ICCs of .987 and .984, respectively. Optoelectronic volumetry was the fastest method, representing a mean total time of 1 minute and 43 (+/- 26) seconds for performing a bilateral measurement. The least limitations were reported on the calculated volume based on the circumference method (3 out of 12 limitations). Conclusion: Calculated volume based on arm circumferences is the best measurement method for evaluating excessive arm volume over time in terms of reliability, low error rate, low cost, few limitations and the time spent.