Appendix A: Body Surface Area and Surface-to-Weight Formula
1) Surface Area Formula
The Surface area of your skin can be calculated using body height (in m2) and weight (in kg) with the formulae:
Body Surface Area (BSA) calculation (in m2)
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•
•
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Formula 1: BSA (m2) = 0.007184 x Height(cm)0.725 x Weight(kg)0.425
(Plug in cm, output is in m) Dubois & Dubois (1916)
Formula 2: BSA (m2) = Square root of [(weight[kg] · height[cm])/3600]
(Plug in cm, output is in m) After Mosteller
Formula 3: BSA (m2) = 0.20247 x Height(m)0.725 x Weight(kg)0.425
After Dubois & Dubois (1916)
Other formula available here: https://en.wikipedia.org/wiki/Body_surface_area#Average_values
Body Surface Area (BSA) – Children (Plug in cm, output is in m2)
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•
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BSA (m2) = (weight[kg] + 4) / 30 [For between 3-30 kg weight]
BSA (m2) = [0.024265 · height[cm]0.3964 · weight[kg]0.5378]
BSA (m2) = [(weight[kg] · height[cm])/3600]1/2
Normal BSA values
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Average BSA for neonate (newborn): 0.25 m²
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Average BSA for child of (2 years): 0.5 m²
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Average BSA for child (9 years): 1.07 m²
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Average BSA for child (10 years): 1.14 m²
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Average BSA for child (12-13 years): 1.33 m²
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"Normal" BSA for adults generally taken to be 1.7 m².
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Average BSA for men: 1.9 m²
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Average BSA for women: 1.6 m²
Source:
Wikipedia.org (2007). Body surface area. Retrieved from
https://en.wikipedia.org/wiki/Body_surface_area#Average_values
2) Surface-to-Weight Ratio
Surface/weight ratio=body surface area (m2)/body weight (kg)
3) A number of online calculators are available. Search these key words: BSA OR body surface area AND
calculator.
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You might try to determine which formula was used.
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You can double check your calculations
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Use for children: http://nicutools.org/MediCalcs/BSA.php3
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Use for adults: http://www.calculator.net/body-surface-area-calculator.html
Appendix B: Practice Calculations
Surface Area Calculations
Adult Males
Calculate the relative surface areas of the following humans: Two men are 1.70 m tall, but one weighs 90 kg, the other
60 kg. Calculate the body surface area (BSA) using these two methods: use one of the formulae provide and then
compare with the value determined by using the adult nomogram.
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The method used in the nomogram requires you to use a straight-edge ruler (e.g.; piece of paper).
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Line the straight-edge on the correct value in the left column (height) and in the column on the right (weight).
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Read the value in the middle column where the straight-edge crosses the line as the calculated value
2. Next, calculate the Surface-to-Weight Ratio for each male subject.
1.
Question 1: Adult calculations (1.2 points total)
Choice 1: Using one of the adult formulae provided (0.8 points) -- Remember metric
Which formula was used (check one):  Formula 1  Formula 2  Formula 3  Other (specify) _________________
Male #1
Male #2
Height (m)
1.70 m
1.70 m
Weight (kg)
90 kg
60 kg
BSA (m2) (Adult Formula)
__________
__________
Surface-to-Weight Ratio (m2/kg)
__________
__________
Choice 2: Using the adult nomogram (0.2 points) -- Remember metric
Male #1
Male #2
Height (m)
1.70 m
1.70 m
Weight (kg)
90 kg
60 kg
BSA (m2) (Adult Nomogram)
__________
__________
Choice 3: Using an online calculator (0.2 points) -- Remember metric
Height (m)
Weight (kg)
BSA (m2) (Adult Calculation)
Male #1
1.70 m
90 kg
__________
Male #2
1.70 m
60 kg
__________
Answer these questions associated with these calculations . (0.6 points total)
1.
Where there significant differences between the formula, the nomogram, and the calculator BSA values?(0.2 points)
2.
Do the results surprise you, or did they fit your expectations? Why or why not? (0.2 points)
3.
Why would one use both methods? Is there a research circumstance where the nomogram may be preferred (Assume
both methods are equally accurate)? (0.2 points)
Question 2: Children from different geographic regions (4.4 points total)
Calculate or determine the same for children age one year from different regions of the world by using their body height and weight as
listed below (see Tables 1-3).
Table 1: Height and weight of one-year-old infants (Using formula for children) – (3 points) -- Remember metric
Group
Pakistani, East
Javanese, rural
Inuit, Alaska
Costa Rican, rural
Australian aborigine
Russian, Minsk
Tasmanian
Average
Height (m)
0.6604
0.6760
0.7110
0.7240
0.7260
0.7370
0.7595
__________
Weight (kg)
6.94
7.53
10.70
8.94
8.44
9.80
10.50
__________
BSA (m2) (Formula)
__________
__________
__________
__________
__________
__________
__________
__________
Surface-to-Weight Ratio (m2/kg)
__________
__________
__________
__________
__________
__________
__________
__________
Table 2: Height and weight of one-year-old infants (Using child nomogram) – ( 0.7 points) -- Remember metric
Group
Pakistani, East
Javanese, rural
Inuit, Alaska
Costa Rican, rural
Australian aborigine
Russian, Minsk
Tasmanian
Height (m)
0.6604
0.6760
0.7110
0.7240
0.7260
0.7370
0.7595
Weight (kg)
6.94
7.53
10.70
8.94
8.44
9.80
10.50
BSA (m2) (Nomogram)
__________
__________
__________
__________
__________
__________
__________
Table 3: Height and weight of one-year-old infants (Using online calculator) – (0.7 points) -- Remember metric
Group
Pakistani, East
Javanese, rural
Inuit, Alaska
Costa Rican, rural
Australian aborigine
Russian, Minsk
Tasmanian
Height (m)
0.6604
0.6760
0.7110
0.7240
0.7260
0.7370
0.7595
Weight (kg)
6.94
7.53
10.70
8.94
8.44
9.80
10.50
BSA (m2) (Nomogram)
__________
__________
__________
__________
__________
__________
__________
(After Meredith, 1978)
Answer these questions associated with the calculations. (1.8 points)
1.
Were the values the same when using the formula as compared to the nomogram and the online calculator? (0.2 points)
2. In comparisons with the adults in Question 1, are any children in general cold or heat adapted? If you answered yes, which
children among the seven groups above can be described as cold, which can be called heat-adapted? (0.4 points)
3. Calculate the Chi-square value, using Table 1 BSA average as expected and Table 2 or 3 data as observedBe sure to include the
determination as part of your answer. .(1.2 point).
Appendix C: Adult Nomogram for Calculating Body Surface Area
Required: Visit this link and print the nomogram: http://www.smm.org/heart/lessons/jpgs/nomogram_adult.jpg
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Appendix D: Child Nomogram for Calculating Body Surface Area
Required: Visit this link and print the nomogram:
http://www.smm.org/heart/tools/Images/nomogram_child.jpg
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Appendix E: Skin Fold Tables for Males and Females (Adults)
Required: Print Tables A and B of this caliper manual:
http://www.cynthiaclarke.com/anth215/215_Assignments/4_Cold/Caliper_Manual.pdf
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Appendix F: Human Adaptation
Required: Visit and read these links as your Appendix F: http://anthro.palomar.edu/adapt/adapt_1.htm and this
link: http://anthro.palomar.edu/adapt/adapt_2.htm
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Appendix G: The Lewis Hunting Effect
Required: Read this recent commentary, and review the review.
Actual data from a lab (Clarke’s Data)