Columbia University

Validation Studies
and
Measurement Technology
BC 420 MA
TANITA R&D : Miyuki Kodama (Nishizawa)

VALIDATION STUDIES
Joint research institutions;
Visceral
adipose
tissue
Obesity Research Center, St. Luke’s/Roosevelt Hospital,
College of Physicians and Surgeons, Columbia University,
New York, USA
Div. of Diabetes and Endocrinology, Jikei University,
Tokyo, Japan
Queen’s University, Kingston, Ontario, Canada
Division of General Internal Medicine Northwestern
University Medical School, USA
Nutrition and Health Research, MRC Human Nutrition
Research, Cambridge, UK
Pediatric Unit, Verona University Medical School, Verona,
Italy

Measurements
Bioelectrical impedance: (Tanita Corp.)
References for Fat, Muscle and Bone : Dual energy X-ray Absorptiometry
(DXA)
References for Total Body Water : D 2
O Dilution method
References for Basal Metabolism : Breath by Breath Pulmonary Gas
Exchange (Indirect calorimetry)
References for Visceral Fat area : Magnetic Resonance Imaging (MRI)
Computed Tomography (CT)
Analysis for accuracy
Paired T-test: to compare between measurement differences, References
measurements vs BIA
Simple linear regression analysis
Bland-Altman: to check for between-method

Dual energy X-ray absorptiometry
(DXA)
Use X-rays of 2 kinds of energy. From the difference in transmission between
them, measure the bone salt percentage, fat percentage and fat free mass
percentage.

Bio Impedance Analysis
Allow a weak current (which is safe for human
body) to flow through the body, and measure the
potential on the current path for obtaining an
impedance.
Toe
Abdomen area
Current
Heel
Current
path
V
Voltage measure

Principle of BIA (Cylindrical model)
Suppose the human body consists of fat free
mass with a resistivity of ρ and fat with ∽.
Given the cross-sectional area is S, the
length L, and the volume V.
Resistance R = ρ L/S. Multiply the right
side by L/L to obtain:
R = ρL 2 /SL = ρL 2 /V
Hence,
V = ρL 2 /R
It implies the water percentage in the body.
Because
density = weight/V,
it can be expressed by:
density = weight × R/ρL 2
Current
脂 Fat 肪 組 織
Fat 除 free 脂 肪 mass 組 織
L

Validation study for estimate
of Visceral adipose tissue
accumulation

The accumulation position of visceral
adipose tissue
Visceral Adipose
Tissue area by CT
or MRI at L4-L5
of Lumbar
vertebra
「Total 「Total Visceral Visceral
Adipose Adipose
tissue」 tissue」
2002.23-37 “Nutrition Week” Poster announcement by Dr.Heymsfield

Visceral-fat by abdomen CT
MALE BMI 25
(Age 27)
MALE BMI 25
(Age 61)

Profile of Subject (NY:American)
AGE
Height
Weight
BMI
Male n=123 Female n=205
42 42 ± 15.7 15.7 48 48 ± 18.7 18.7
20~83 20~83
18~94 18~94
177.0 177.0 ± 6.9 6.9 162.1 162.1 ± 7.0 7.0
159.9~191.5
143.1~182.6
81.1 81.1 ± 12.2 12.2 70.0 70.0 ± 15.4 15.4
47.4~108.2
40.6~111.3
25.8 25.8 ± 3.4 3.4 26.7 26.7 ± 5.5 5.5
17.1~33.3 17.1~33.3
16.9~40.9 16.9~40.9

Profile of Subject (Japanese)
AGE
Height
Weight
BMI
Males n=157 Females n=169
41.2±13.4 49.4±17.0
19~69
19~84
169.2±6.6 154.0±6.3
144.5~183.2
138.7~170.0
68.3±11.3 56.4±11.6
43.7~104.3
39.3~106.0
23.8±3.4 23.1±4.9
17.7~36.9
16.8~42.9
Clinical inspection, such as blood biochemistry inspection,
was performed to 50 male and 60 female among this subject.

Correlation between Estimated VAT by
regression formula from BIA and VAT by
MRI (NY American)
Male (NY)
Female (NY)
V
V
A
A
T
T
(M
(M
R
R
I)cm
I)cm
2
2
350
350
300
300
250
250
200
200
150
150
100
100
y = 1.0631x - 6.2605
y = 1.0631x - 6.2605
R2 = 0.7058
R2 = 0.7058
R = 0.840
R = 0.840
p

Correlation between Estimated VFA by
regression formula from BIA and VFA by
CT (Japanese)
Male (JPN)
Female (JPN)
VAT
VAT
(CT)cm2
(CT)cm2
350
350
300
300
250
250
200
200
150
150
100
100
y = x + 4E-13
y = x + 4E-13
R 2 = 0 .6 6 2 6
R 2 = 0 .6 6 2 6
R = 0.814
R = 0.814
p

Correlation between VAT by regression
formula and The result of clinical
inspection (Japanese)
Male (n=50)
VAT VAT by by regression regression
VAT VAT by by CT CT
formula formula
r
r p r r p
HBP HBP 0.27
0.27
NS
NS
0.23
0.23
NS
NS
LBP LBP 0.40
0.40
**
**
0.40
0.40
**
**
GOT GOT 0.55
0.55
***
***
0.52
0.52
***
***
GPT GPT 0.47
0.47
***
***
0.53
0.53
***
***
γ-GTP γ-GTP 0.34
0.34
*
*
0.37
0.37
**
**
UA UA 0.22
0.22
NS
NS
0.20
0.20
NS
NS
TC TC 0.12
0.12
NS
NS
0.33
0.33
*
*
TG TG 0.50
0.50
***
***
0.58
0.58
***
***
HbA1c HbA1c 0.48
0.48
***
***
0.38
0.38
**
**
Female (n=60)
VAT VAT by by regression regression
VAT VAT by by CT CT form form ula ula
r
r
p r
r
p
HBP HBP
0.52
0.52
***
***
0.62
0.62
***
***
LBP LBP
0.40
0.40
**
**
0.54
0.54
***
***
GOT GOT 0.45
0.45
***
***
0.49
0.49
***
***
GPT GPT 0.29
0.29
*
*
0.40
0.40
**
**
γ-GTP γ-GTP 0.14
0.14
NS
NS
0.17
0.17
NS
NS
UA UA 0.49
0.49
***
***
0.40
0.40
**
**
TC TC 0.40
0.40
**
**
0.33
0.33
*
*
TG TG 0.55
0.55
***
***
0.52
0.52
***
***
HbA1c HbA1c -0.02
-0.02
NS
NS
0.00
0.00
NS
NS
*:p

Validation study for estimate
of Body Composition
Body inside potassium counting
DXA

Correlation between FATkg by BIA
method and that by DXA method
Fatkg (DXA vs TANITA BIA)
DXA Fatkg
80.0
70.0
60.0
50.0
40.0
30.0
20.0
10.0
y = 0.9788x + 0.1902
R 2 = 0.9238
R = 0.9612
SEE = 2.870
p < 0.0001
n = 1206
0.0
0.0 20.0 40.0 60.0 80.0
Fat kg from TANITA BIA
The institution which collected data : St. Luke’s-Roosevelt Hospital (Columbia University)

Correlation between Muscle kg by BIA
method and that by DXA method
E stim ate d M u sc u le kg
(DXA Lean Soft Tissue vs TANITA BIA)
DXA LST (Muscle) kg
120
100
80
60
40
y = 0.9769x + 1.2902
R 2 = 0 .9 3
R = 0.97
SEE = 2.78
p < 0.0001
MALE
FEM ALE
20
20 40 60 80 100 120
M u sc le kg fro m T A N IT A B IA
The institution which collected data : St. Luke’s-Roosevelt Hospital (Columbia University)

Validation study for estimate of
Basal metabolism
Breath by Breath Pulmonary Gas Exchange : Aero Sport TEEM 100 Metabolic Analysis System

Estimate of Basal metabolism from
Fat Free Mass
• The basal metabolism has heretofore been obtained by
calculation from the body height and weight.
• Suppose the weight of an individual is equal, his consumption
of energy rises as his fat free mass (FFM) increases.
• Therefore, the basal metabolism can be calculated more
accurately from FFM measured by BIA.
Obese person with little
FFM is comparable to a
car of small engine
with a plenty of fuel
Athlete like person with
much FFM is comparable
to a car of poor fuel
consumption rate with
a large engine

Relation between REE( ≒BMR)
and Body Weight
Japan
N.Y.
3000
2500
Male
y = 16.003x + 513.33
R2 = 0.427
R=0.653
3000
2500
Male
y = 17.25x + 427.46
R2 = 0.523
R = 0.723
2000
2000
REE kcal/day
1500
REE kcal/day
1500
1000
1000
500
Female
y = 8.3391x + 715.53
R2 = 0.360
R = 0.600
500
Female
y = 7.9658x + 818.77
R2 = 0.393
R = 0.627
0
30.0 50.0 70.0 90.0 110.0 130.0
Weight kg
0
30 50 70 90 110 130
Weight kg
M
F
M
F

The value of the BMR calculated from
regression formula and analyzed from breath
R E E kc al / day (fro m bre ath )
3000
2500
2000
1500
1000
500
y = x + 9E-11
R 2 = 0 .8 0 8
R = 0.900
SEE = 131.4
p

Validation study for Body
water measurement

Total Body water measurement
60%
General standard value
60%
of Bodyweight
40% ICW
20% ECW
Main functions of water
Controls body
temperature
Conveys
substances
※There is individual difference in fact.
Serves as solvent

Correlation between Total Body Water by BIA
method and that by D 2
O Dilution method
70
60
50
Correlation of TBW by D2O and estimated TBW by
TANITA BIA (n=167)
Male
y = x - 2E-12
R 2 = 0.7791
R = 0.8827
SEE = 2.75
p < 0.0001
TBW (D2O)
40
30
20
Fem ale
y = x + 1E-12
R 2 = 0.7839
R = 0.8854
SEE = 1.9872
p < 0.0001
10
10 20 30 40 50 60 70
TANITA BIA TBW
The institution which collected data : St. Luke’s-Roosevelt Hospital (Columbia University)

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