Functional submersion technique for assessing volume


Evaluations were conducted of 3 successively modified prototypes of a water displacement apparatus (volumeter) designed to measure total body volume. Calibration involved adding known quantities of water to a submersion tank and marking the corresponding water levels on an attached column (manometer) angled 2.5°above horizontal. Containers simulating the volumes of small, medium, and large adults were measured hydrostatically (criterion) and by means of water displacement. Multiple trials were performed on consecutive days using both methods to assess stability reliability and concurrent validity. The smallest manometer graduations corresponded to 0.1 L changes in tank volume. Reliabilities for criterion and displacement (3 prototypes) volumes were high (intraclass r ≃ 1.00). Although criterion and displacement measurements were highly related (r ≃ 1.00), displacement values were comparatively greater (p <. 01) for all three prototypes: ('Δ(M) ± SE(M)) 1.2 ± 0.1, 8.0 ± 0.28, and 1.82 ± 0.08 L. Therefore, simple linear regression was used to predict criterion volumes for each of the volumeters. In all cases, mean differences between predicted and criterion volumes were negligible. Consequently, it appears water displacement incorporating low-angle manometers may be a useful alternative to hydrostatic weighing for assessing the volumes of human-sized objects. © 2000, Lawrence Erlbaum Associates, Inc.

Publication Title

Measurement in Physical Education and Exercise Science