The reliability of a simplified water displacement instrument: a method for measuring arm volume.
OBJECTIVE
To present a new water displacement measurement, the Simplified Water Displacement Instrument (SWDI), and to evaluate its intra- and intertester reliability.


METHODS
Reliability design.


METHODS
Hospital setting.


METHODS
Fifty-six healthy people were studied. Intratester reliability was evaluated once a week for 4 weeks in 20 women and 10 men. Intertester reliability was assessed by 2 physical therapists in 26 people.


METHODS
Not applicable.


METHODS
Coefficients of variation (CVs) and intraclass correlation coefficients (ICCs).


RESULTS
The intratester reliability showed a CV range of 2.2% to 2.6% and an ICC range of .98 to .99. The intertester reliability showed a CV of 1.3% and an ICC of .99. There was a significant increase in arm volume in men compared with women. There were no significant differences in changes in volume over the 4 weeks. There was a significant greater right arm volume (3.3%) among the right-handed subjects (P<.001).


CONCLUSIONS
Both intra- and intertester reliability were satisfactory for the SWDI.
Sagen
Ase
A
Ulevaal University Hospital, Oslo, Norway. aase.sagen@ulleval.no
Kåresen
Rolf
R
Risberg
May Arna
MA
D000368:Aged; D000886:Anthropometry / Q000295:instrumentation*; D001132:Arm / Q000033:anatomy & histology*; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009929:Organ Size; D012016:Reference Values; D015203:Reproducibility of Results; D014867:Water
D014867:Water