Background: Assessment of waist circumference
is being emphasized for the evaluation of fat
distribution. InBody 3.0, a body composition
analyzer device, automatically measures waist
circumference, hip circumference, and waist-hip ratio
(WHR), thus its results are widely utilized due to its
convenience. The purpose of this study was to assess
the accuracy of the waist circumference, hip
circumference, and WHR measurements obtained
through InBody 3.0.
Method: The participants involved 345 patients
who visited the obesity clinic in a hospital and had
been evaluated by InBody 3.0. Waist circumference
(midpoint between the lower border of the rib cage
and the iliac crest; umbilical level; top of the iliac
crest) and hip circumference (the widest area of the
buttock) were measured manually by a single trained
personnel. The waist, hip circumferences, and WHR
obtained by InBody 3.0 were compared with the
waist, hip circumferences, and WHR obtained by
manual unelastic tape measurement.
Results: The waist circumference obtained by
inbody 3.0 was significantly greater than the
manually measured values at three different levels by
7.81±5.72 cm, 4.20±6.51 cm, 4.68±5.99 cm; waist to hip ratio was also shown to be greater by 0.067±
0.060, 0.031±0.063, 0.036±0.060 at each levels of
waist measurement and this difference increased in
proportion to BMI of the subjects (p<0.05). The false
positive rate for assessment of abdominal obesity by
the InBody 3.0 was 7∼17% presuming that the
abdominal obesity according to manual measurement
of waist circumference and WHR were golden
standards.
Conclusion: Despite the convenience of the
automatic measurement of waist circumference and
WHR obtained by InBody 3.0, it had a tendency to
overestimate the values. The importance of manual
tape measurement in order to accurately evaluate fat
distribution and abdominal obesity must be
emphasized.

Keywords: Waist circumference, Waist to hip ratio, Accuracy, Body composition
analyzer