Lecture 4: Interpreting Anthropometric Data

Question 1

What are some measurements of body size?

Answer 1

• Weight
• Height
• Elbow breadth
• MUAC
• Head circumference
• Length

Question 2

What do head circumferences measure?

Answer 2

Brain growth

Question 3

At age two what do we switch?

Answer 3

From measuring lying down to standing up

Question 4

What fraction of people in NZ are of a healthy weight?

Answer 4

1/3

Question 5

What BMI indicates normal weight?

Answer 5

18.5 - 24.9

Question 6

What BMI indicates you are overweight?

Answer 6

25.0 - 29.9

Question 7

What BMI indicates mild obesity?

Answer 7

30.0 - 34.9

Question 8

What BMI indicates moderate obesity?

Answer 8

35.0 - 39.9

Question 9

What BMI indicates extreme obesity?

Answer 9

> 40.0

Question 10

What is metabolic syndrome a straight forward term to describe?

Answer 10

Increased BP, glucose, TAG’s, reduced HDL cholesterol

Question 11

What is sensitivity?

Answer 11

How good a measure/test is at correctly identifying people who have the disease

Question 12

What is normal waist circumference range?

Answer 12

Men: 94 - 102cm
Women: 80 - 88cm

Question 13

What is abnormal waist circumference range?

Answer 13

Men: >102cm
Women: >88cm

Question 14

What are growth indices derived from?

Answer 14

A combination of raw measurements (e.g. “weight-for-height”)

Question 15

What are growth indices used to compare?

Answer 15

Individuals/groups with a growth chart or reference data

Question 16

What is occipital frontal circumference (OFC)?

Answer 16

Using flexible, non-stretch tape over the most prominent part on back of head (occiput) and just above the eyebrows (supraorbital ridges)

Question 17

What measurement does OFC give?

Answer 17

The largest circumference of the head

Question 18

What can head circumference show in under 2’s?

Answer 18

• Index of chronic protein-energy deficiency
• Brain development

Question 19

What is wasting?

Answer 19

“acute malnutrition” - because it is believed that episodes of wasting have a short duration

Question 20

What is stunting?

Answer 20

“chronic malnutrition” - longer duration

Question 21

What is weight-for-age used to assess?

Answer 21

over- or under-nutrition

Question 22

What is a limitation of weight-for-age?

Answer 22

• can’t distinguish tall thin children who are underweight from those who are short with adequate weight

Question 23

What is under-nutrition under-estimated?

Answer 23

If rates of stunting are high but rates of wasting are low

Question 24

What infants and children can be measured by length?

Answer 24

< 85cm

Question 25

How is length measured?

Answer 25

Using a calibrated length board - measure without shoes, wearing light underclothing or nappy

Question 26

What is weight-for-height?

Answer 26

assesses a person’s body weight relative to their height

Question 27

What does low weight-for-height in low income countries indicate?

Answer 27

“wasting” (failure to gain sufficient weight relative to height)

Question 28

What does low weight-for-height in high income countries indicate?

Answer 28

Growth faltering and wasting in hospital patients

Question 29

What are limitations of weight-for-height?

Answer 29

Need to also use height-for-age:
- Could be stunted
- Oedema

Question 30

What is height-for-age an index of?

Answer 30

Past nutritional status

Question 31

What is stunting due to?

Answer 31

Extended period of inadequate food supply, poor dietary quality - causes increased morbidity in childhood (2nd or 3rd yr of life)

Question 32

What is reference data used to do?

Answer 32

• Facilitate international comparisons
• Evaluate trends over time
• Evaluate effectiveness of intervention programmes

Question 33

How is reference data used in clinical settings?

Answer 33

• Monitor growth
• Identify under- or over- nutrition
• Assess response to treatment

Question 34

A growth standard is NOT a….

Answer 34

Growth reference

Question 35

What is a growth reference?

Answer 35

Growth pattern of healthy population

Question 36

What is a growth standard?

Answer 36

Recommended pattern of growth - specific health outcomes and decreased long term health risks

Question 37

BF babies grow similarly or faster in the 1st 2-3 months and then…

Answer 37

Grow less rapidly compared to formula fed babies

Question 38

What is the WHO growth standard for overweight (<5 yrs of age)?

Answer 38

wt-for-ht z-score of over 2

Question 39

What is the WHO growth standard for obesity (<5 yrs of age)?

Answer 39

wt-for-ht z-score of over 3

Question 40

Which growth standard is the best?

Answer 40

WHO - choose one method and stick with it

Question 41

What is reference data used to generate?

Answer 41

• Percentiles
• Z-scores

Question 42

When should percentiles be used?

Answer 42

in high income countries

Question 43

When should z-scores be used?

Answer 43

especially in low income countries, but also high income countries

Question 44

What percentiles indicate individuals at risk?

Answer 44

Below the 3rd/5th percentiles or above the 97th/95th percentiles

Question 45

When should percentiles not be used?

Answer 45

For individuals/populations from low-income countries if using reference data from high income countries

Question 46

What does a z-score tell us?

Answer 46

How many standard deviations an individuals measurement is away from the population mean

Question 47

What does a standard deviation tell us?

Answer 47

About the spread of our data around the mean

Question 48

The higher spread or variability….

Answer 48

the higher the standard deviation

Question 49

Z-score equation:

Answer 49

Z-score = (persons measurement - reference mean) / reference SD

Question 50

What does a z-score of 0 mean?

Answer 50

It is on the mean/median