Reliability, concurrent validity and clinical feasibility of measurement methods determining local tissue water in...

To investigate reliability, concurrent validity and clinical feasibility of local tissue water measurements in patients with lower limb lymphedema and healthy controls.

In this cross-sectional study the Moisture Meter D Compact device^® (MMDC) measurement and "pitting test" were performed three times by two assessors to test intra- and inter-rater reliability in 47 patients and 30 healthy controls. To investigate the between-session reliability, 29 patients and 21 healthy controls were reassessed two weeks later. Time efficiency and practical limitations were evaluated. The concurrent validity was investigated between the two tests. Clinical trial registration number: NCT:05269264.

Of the MMDC values, 58% showed strong to very strong intra-rater reliability, 32% showed strong to very strong inter-rater reliability and 36% had strong to very strong between-session reliability. Absolute values had generally a higher reliability than inter-limb or leg-to-arm ratio values. The pitting test had nil to perfect agreement between assessments (Cohen's kappa = -0.03-1.00) with fewer practical limitations and shorter performance time than the MMDC. Between both tests nil to a moderate relationship was found (Kendall's tau c = 0.00-0.60).

The MMDC and pitting test are reliable and feasible measurements to assess local tissue water depending on the location, but should not be used interchangeably.