TROIKA REPORT 1
RELIABILITY OF SKINFOLD MEASUREMENTS
Work together in your Troika to produce one printed report
due at the beginning of your Lab session Monday June 29th.
By the same deadline email the WORD file of your report to ward@sfu.ca
Download a copy of the EXCEL file Skinfold 152.xlsx containing the class skinfold measurements from the
BPK 303 web page. Using this data you will calculate and interpret the TEM and %TEM for each of the
skinfold measures (Trials 1, 2 and 3 combined) for each sex for your class data this semester.
Your report on this analysis must have the following sections and format:
FORMAT
Font: 12pt Arial.
Separate title page
Introduction through to Discussion double spaced, paged and numbered continuously.
References single spaced on a separate page.
Report means and TEMs etc. to one decimal place (e.g. 15.2).
Marks will be given for formatting (5 marks).
TITLE PAGE: Must include an overall title for the report, your names, student numbers, Troika IDs and date
of submission on a separate first page. (5 marks)
INTRODUCTION: Provide a background to the assessment of the reliability of anthropometric measures by
reviewing the reported scientific literature on the use of TEM and %TEM that you have found. At the end of
your introduction provide a statement of the purpose of this investigation. Make reference to any pertinent
literature you have found on the use of technical error of measurement. (20 marks)
METHODS: A description of the subjects, measurement procedures and details of the analysis carried out.
Just name the anthropometric measures used and reference the exact techniques in the Anthropometry
Chapter 2 of the course readings. Describe what was done in your study in enough detail that someone could
replicate it. (10 marks)
RESULTS: Produce a well formatted table of the results (as shown below in Table 1 below) with an
appropriate caption (title) such that the table could stand alone. The Caption must be at the top of the table.
If variable name abbreviations are used, the full name must be in a table footnote, or the table caption.
Write text for the results section that tells the “story” of your results without interpretation. This will be quite
brief but must be included. The table should be in-line with the results text not on its own page at the end of
the document. (20 marks)
n.b. There may well be entry blunders in the data. Do not change or omit any data. Analyse it “as
is”, but report any anomalies you notice.
BPK 303 – Kinanthropometry – Summer 2015 – Dr. Richard Ward
Included below are the results of the same analysis from a previous semester (Table 1). Do not interpret
this data, it is included to illustrate the type of table you are trying to produce from your calculations on your
current class data.
Table 1: Mean Skinfold Thicknesses, Technical Errors of Measurement and % Technical Errors of
Measurements for Skinfolds calculated on the class data for the Spring of 1998. All measurers were
combined in the analysis.
Females
TPSF
BISF
SSSF
FASF
ILSF
SPSF
ABSF
FTSF
MCSF
Sample Size
Mean Skinfold
Thickness (mm)
Sum of Squared
Differences
Technical Error of
Measurement (mm)
% Technical Error of
Measurement
28
28
28
28
28
28
28
28
28
17.2
10.0
15.0
15.4
19.2
13.2
19.3
23.7
16.1
387.2
206.7
205.7
234.2
346.1
112.4
447.7
289.0
190.8
2.6
1.9
1.9
2.0
2.5
1.4
2.8
2.3
1.8
15.1
19
12.7
13.3
13
10.6
14.5
9.7
11.2
Males
TPSF
BISF
SSSF
FASF
ILSF
SPSF
ABSF
FTSF
MCSF
Sample Size
Mean Skinfold
Thickness (mm)
Sum of Squared
Differences
Technical Error of
Measurement (mm)
% Technical Error of
Measurement
25
25
25
25
25
25
25
25
25
15.2
9.8
14.0
13.2
17.9
12.7
18.1
21.7
15.4
27.0
37.3
24.9
176.4
374.3
365.9
117.5
318.4
74.5
0.7
0.9
0.7
1.9
2.7
2.7
1.5
2.5
1.2
4.6
9.2
5
14.2
15.1
21.3
8.3
11.5
7.8
TPSF=Triceps Skinfold, BISF=Biceps Skinfold, SSSF=Subscapular Skinfold, FASF = Forearm Skinfold, ILSF=Iliac Crest Skinfold,
SPSF=Supraspinale Skinfold, ABSF=Abdominal Skinfold, FTSF=Front Thigh Skinfold, MCSF=Medial Calf Skinfold
DISCUSSION: Provide an interpretation of the meaning of the results you have found. Comparison to
typical values for criterion measurers of these measures (as shown below) should be included. In addition
find other sources of typical TEM values for these types of measurements reported in the scientific
literature. You do not have to find TEMs for each specific skinfolds used here, sometimes only a few of
these may appear in an article or you may find that one value of %TEM is given for skinfolds in general. (20
marks)
REFERENCES: References must be listed in a consistent format. These will be all the TEM references you
have found and Chap 2 Anthropometry from the course readings. It does not matter which style you choose
but bear in mind that the same reference will look different in different styles. (10 marks)
Style of Journal of the American Medical Association
1. Armellini F, Zamboni M, Frigo L, et al. Alcohol consumption, smoking habits and body fat
distribution in italian men and women aged 20-60 years. Eur J Clin Nutr. 1993;47(1):52-60.
Style of American Journal of Physical Anthropology
Armellini F, Zamboni M, Frigo L, Mandragona R, Robbi R, Micciolo R, Bosello O. 1993. Alcohol
consumption, smoking habits and body fat distribution in italian men and women aged 20-60 years.
Eur J Clin Nutr 47(1):52-60.
For more information on appropriate writing style go to:
BPK 303 – Kinanthropometry – Summer 2015 – Dr. Richard Ward
http://abacus.bates.edu/~ganderso/biology/resources/writing/HTWtoc.html
Sample TEM Results Table
In your discussion of the meaning of the %TEMs that you have calculated you can refer to the values in
Table 2, that illustrate typical %TEM values obtained by accomplished anthropometrists in addition to the
values you have found in the literature. They are not to be used as exact cutoffs for acceptance but as
general indications of the precision required in reliable measurement.
Table 2: Typical %TEMs for accomplished anthropometrists for various measurements
Measurement Type
Direct Lengths
Skinfold
Thicknesses
Girths
Breadths & Depths
Measurement
Upper Arm (Acromiale-Radiale)
Forearm (Radiale-Stylion)
Hand (Midstylion-Dactylion)
Thigh (Trochanterion-Tibiale Laterale)
Lower Leg (Tibiale Mediale-Sphyrion Tibiale)
Foot
Triceps
Subscapular
Biceps
Iliac Crest
Supraspinale
Abdominal
Front Thigh
Medial Calf
Arm (relaxed)
Forearm (max)
Wrist
Chest
Waist
Gluteal (Hip)
Thigh
Mid-Thigh
Calf (max)
Ankle
Biepicondylar humerus
Biepicondylar Femur
Wrist
Hand
Biacromial
Biiliocristal
Transverse chest
Anterior-Posterior Chest Depth
BPK 303 – Kinanthropometry – Summer 2015 – Dr. Richard Ward
%Technical Error of
Measurement
Male
Female
0.8
1.4
1.2
0.9
0.5
0.9
3.0
3.6
2.3
6.2
3.4
6.2
4.7
2.8
0.8
0.7
1.0
0.8
0.7
0.7
0.7
0.6
0.3
0.6
1.0
1.0
1.9
2.8
0.95
1.2
1.7
0.7
0.8
1.4
1.2
0.9
0.5
0.9
4.0
3.6
2.9
8.3
4.0
8.7
6.4
4.5
0.8
0.3
1.0
0.8
0.7
0.7
0.7
0.6
0.3
0.8
0.8
0.8
1.9
2.8
0.95
1.2
1.7
0.7
Calculation of Technical Errors of Measurement
You will need to sort the columns in the skinfold file such that trials 1 to 3 of each variable are next to each
other. Under the DATA menu you will find the SORT option. Click this and the SORT dialog box will open
(Figure 1). Make sure before you do this that you have selected all the columns that you need to be sorted.
Now click on the OPTIONS button and select “sort left to right”. Click OK and you will be returned to the
SORT dialog box. Make sure that it says Sort by Row 1 (this is the row with your variable names in) and
then click OK. The columns will now be sorted alphabetically which will cause them to be sorted by trial
within variable name.
Figure 1: Sort dialog box found under the DATA menu
Now you can calculate the TEMs for the
skinfolds. Copy the three trials for one of
the skinfolds, for one sex, and paste it in
the top corner of a new spreadsheet
Figure 2). Then turn the three columns
into two columns by linking the data by
equation into the two columns as
illustrated below. Note that trial 1 (red)
vs trail 2 (blue) is the first pairing. Below
that is trial 1 (red) vs trial 3 (green), and
below that is trial 2 (blue) vs trial 3
(green). You have essentially turned
three trials into two trials with three
times the sample size.
The calculation of TEM can now be
achieved by first calculationg the
squared differences of all I vs II pairs.
(=(E2-F2)^2). Copy this equation down
for all pairs. Now calculate the sum of
these squared differences
Figure 2: EXCEL spreadsheet set up for TEM calculation
(=sum(G2:G28)). Technical error of
measurement is then the square root of
the sum of squared differences divided by 2n. Not that we inflated the n 3 times as we put three columns
into 2 so we need to multyiply the sample size by 3. In this example the sample size n is 9. Thus TEM =
SQRT(sum(G2:G28)/(2*3*9)).
BPK 303 – Kinanthropometry – Summer 2015 – Dr. Richard Ward
The %TEM requires the calculation of the mean of all of the trials for the skinfold which is then divided into
the TEM and multiplied by 100.
BPK 303 – Kinanthropometry – Summer 2015 – Dr. Richard Ward