Seca 515 - Manual (Page 46)

46 •
Therefore, seca has developed in-house prediction formulas for
calculating the following parameters for the arms and legs:
• Total body water (TBW)
• Extracellular water (ECW)
• Fat-free mass (FFM)
• Lean soft tissue (LST) for the arms and legs
In-house reference values were determined for the following parameters in
order to be able to show normal ranges:
• Bioelectric impedance vector analysis (BIVA)
• Mass indices (FMI, FMMI)
• Phase angle (Φ)
In order to calculate the formulas and reference values, there was close
collaboration with the Institute for Human Nutrition and Food Studies at
the University of Kiel and a joint representative study was performed.
In contrast to all formulas published so far, the seca in-house formulas are
population-specific. The formulas developed in Kiel are valid for
Caucasian population groups only.
Representative surveys were also performed in the USA in collaboration
with the New York Obesity Nutrition Research Center at the St. Luke’s
Roosevelt Hospital. seca in-house formulas for African, South and Central
American, and Asiatic population groups were developed on the basis of
this study.
The seca in-house formulas are implemented for seca mbca devices
andseca PC software only. As such, seca is a pioneer in the well-founded
scientific and medically significant determination of the body composition
by means of bioelectric impedance analysis.
8.2 Evaluation modules
Summary of the evaluation modules At seca, we call all the variables required to assess body composition
"evaluation modules". The following table offers an overview of the
evaluation modules of the
seca 515/514 :
Evaluation
module
Display Diagnostic relevance
Bioelectric
impedance
vector analysis
(BIVA)
• Normal range display of R and X
c
in
coordinate system in relation to body
size
• 50%, 75%, 95% percentiles as
tolerance ellipses
• Assessment of the quantity of total body water and
body cell mass
• Monitoring of changes in both quantities
Body Mass
Index (BMI)
• Absolute in kg/m
2
• Display for children in percentile
curves
• For adults: Graphic display of WHO
reference values
• Classification option into normal, overweight,
underweight, and obese
• This is dependent on age and gender in children
Extracellular
water (ECW)
Absolute in l
Differentiated view of changes in total body water
Possible cause of increase in ECW: Storage of fluid in
extracellular area
Fat-free mass
(FFM)
Absolute in kg
A decrease in fat-free mass indicates a decline in the
health of seriously ill and overweight people.
Fat mass (FM)
• Absolute in kg
• Relative in %
• For adults: Normal range display
• Determination of energy resources in underweight and
heavily overweight patients
• Study of change in fat mass whilst undergoing medical
treatment or as a disease progresses