Estimates for Assessment of Lymphedema: Reliability and Validity of Extremity Measurements.

Background: Measuring lymphedema with high accuracy is important for several reasons. The aim of this study was to assess the reliability and validity of three routinely used methods to estimate limb volumes. Methods and Results: Inverse water displacement, girth measurements, and Perometer measurements were executed. Although standard techniques were used, extra precautions were taken to maximize accuracy within and between observers. Water displacement, and girth and Perometer measurements resulted in standard deviations of 0.7%-0.8%, 0.5%, and 0.4%-1.0%, respectively. Conclusion: Measuring limb volumes using routine methods is not easy. Even under optimal conditions, the measurements are quite dependent on the observer. For practical situations, an easy, objective, and reliable method is lacking.