NUTRITIONAL ASSESSMENT BY

USING ANTHROPOMETRY AND BMI

Md. Moksed Ali PramanikPrincipal Research Associate

INFS University of Dhaka

Nutritional Assessment: Nutritional Assessment is the evaluation of individual nutritional status.

Types or Methods of Assessment

Direct Indirect

Clinical Biochemical Biophysical Anthropometry

Food Consumption / Dietary Survey Nutritional Epidemiology

Anthropometric Assessment:

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For Anthropometric Assessment, information is needed on each individual’s sex, age, weight, height, Mid Upper Arm Circumference etc.

Anthropometric Data Analysis:

The anthropometric data were calculated and analyzed as standard deviation scores (Z-scores) of NCHS (The US National Center for Health Statistics) reference height-for-age, weight-for-age and weight-for-height and as percentage of reference median of these indicators. The Anthro software package and Epi Info were used in this regard.

Z-score (Standard Score): Z-score is simple a position score in terms of standard vdeviation with reference to the mean.

Individual’s value ─ Mean value x = ∑ x I ÷ n Z score = ------------------------------------------------------------------ SD = ∑ √ ( x i ―x)2 ÷ (n ― 1) Standard deviation = √ 1 [ ∑ xi

2 ―(∑xi)2 ]

There are three categories of z-score for Anthropometric Data Analysis. They are as follows

HAZ (Height for age z-score) – Measures Stunting

Low HA is considered an indicator of stunting (i.e. shortness) which is frequently associated

with poor overall economic condition and/or repeated exposure to adverse condition. (past

chronic under nutrition)

WAZ (Weight for age z-score) – Measures Underweight

WA is primarily a composite of WH and HA, and fails to distinguish tall, thin. Children from

short, well proportioned children (stunting wasting / current acute and chronic under

nutrition).

WHZ (Weight for height z-score) – Measures Wasting

Low WH is considered an indicator of wasting (i.e. thinness) and is associated with failure

to gain weight or a loss of weight.

(Individual’s height) ─ (Mean or median height of reference for given age and sex)HAZ = --------------------------------------------------------------------------------------- Standard deviation of reference

Cut-off point of HAZ –

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HAZ < 3 SD : Severely stuntedHAZ < 2 SD to 3 SD : Moderately stuntedHAZ ≥ 2 SD : Not stunted

(Individual’s weight) ─ (Mean or median weight of reference for given age and sex)WAZ = --------------------------------------------------------------------------------------- Standard deviation of reference

Cut-off point of WAZ

WAZ < 3 SD :Severely underweightWAZ < 2 SD to 3 SD : Moderately underweightWAZ ≥ 2 SD : Not underweight

(Individual’s weight) ─ (Mean or median weight of reference for given sex and height)WHZ = --------------------------------------------------------------------------------------- Standard deviation of reference

Cut-off point of WHZ WHZ < 3 SD : Severely wastedWHZ < 2 SD to 3 SD : Moderately wastedWHZ 2 SD & WHZ < + 2 SD : NormalWHZ + 2 SD to + 3 SD : Over-weightWHZ > + 3 SD : Obese

Epi info software G 18 eQi eqm ch©š— †Q‡j ‡g‡q‡`i HAZ Ges WAZ calculate Kiv hvq| WHZ Gi †¶‡Î †Q‡j‡`i eqm 11.5 eQi Ges D”PZv 145 †m.wg Gi Kg Ges †g‡q‡`i Rb¨ 10 eQi Ges D”PZv 137 †m.wg. Gi Kg| D”PZv 49 †m.wg. Gi Kg n‡j WHZ calculate Kiv hvq bv| (HAZ and WAZ of children aged up to 18 years can be calculated by using Epi Info software. WHZ of boys aged 11.5 years and height less than 145 cm. and for girls aged 10 years and height less than 137 cm can be calculated. When height less than 49 cm. WHZ can not be calculated.

Weight for-age percent of median (WAM) (PEM or Gomez Classification):

Percent Expected weight for age

Classification Category of Nutritional status

Weight for-age percent of median (WAM) > 90 %

Normal Normal

Weight for-age percent of Mild malnutrition 1st degree

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median (WAM) 76-90 % malnutritionWeight for-age percent of median (WAM) 61-75 %

Moderate malnutrition

2nd degree malnutrition

Weight for-age percent of median (WAM) ≤ 60 %

Severe malnutrition

3rd degree malnutrition

Wellcome Classification

Percent Expected weight for age

Edema present Edema absent

WAM 60-80 % Kwashiorkor UnderweightWAM < 60 % Marasmic-Kwashiorkor Marasmus

In Waterlow classification children are categorized into four groups on the basis of percentage deviation from the reference median height-for-age and weight-for-height. The following cut-off points were used to categories normal, stunted, wasted and stunted & wasted:Normal : Height-for-age 90 % of reference median

Weight-for-height 80 % of reference median

Stunted : Height-for-age < 90 % of reference median Weight-for-height 80 % of reference median

Wasted : Height-for-age 90 % of reference median Weight-for-height < 80 % of reference median

Stunted : Height-for-age < 90 % of reference medianand wasted Weight-for-height < 80 % of reference median

Degree of Stunting Height for age percent of median (HAM) Category of nutritional statusHAM > 95% Grade ‘0’ or normalHAM 90 – 95% Grade 1 stuntingHAM 85 – 89.99% Grade 2 stuntingHAM < 85% Grade 3 stunting

WAM = (hs ÷ hp) × 100

Where hs = height of the sample

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hp = height of the reference population. Equivalents of percentile and Z-score in normal distribution

Below Mean Above Mean

percentile Z-score percentile Z-score

0.0 to 4.9 - 3.090 to – 1.650 50.0 to 54.9 0.000 to 0.120

5.0 to 9.9 - 1.645 to – 1.290 55.0 to 59.9 0.126 to 0.250

10.0 to 14.9 - 1.282 to – 1.040 60.0 to 64.9 0.253 to 0.380

15.0 to 19.9 - 1.036 to – 0.850 65.0 to 69.9 0.3855 to 0.520

20.0 to 24.9 - 0.842 to – 0.680 70.0 to 74.9 0.524 to 0.670

25.0 to 29.9 - 0.675 to – 0.530 75.0 to 79.9 0.675 to 0.840

30.0 to 34.9 - 0.524 to – 0.390 80.0 to 84.9 0.842 to 1.030

35.0 to 39.9 - 0.385 to – 0.260 85.0 to 89.9 1.036 to 1.280

40.0 to 44.9 - 0.253 to – 0.130 90.0 to 94.9 1.282 to 1.640

45.0 to 50.0 - 0.126 to – 0.000 95.0 to 99.9 1.645 to 3.090

Anthropometric classification for the evaluation of growth and nutritional status

Category Percentile Z –score Growth status

Weight status

Muscle status

Category I 0.0 to 5.0 Z<-1.650 Short Low Weight

Low Muscle Wasted

Category II 5.1 to 15.0 -1.645<Z<-1.040

Below Average

Below Average

Below Average

Category III 15.1 to 85.0 -1.036<Z<+1.030

Average Average Average

Category IV 85.1 to 95.0 +1.036<Z<+1.640

Above Average

Above Average

Above Average

Category V 95.1 to 100.0 Z>+1.645 Tall Heavy Weight

High muscle:Good Nutrition

Table AP9.1: Weight-for-age for young children (birth to 60 months;sexes combined) in kg. (in standard deviations above and below reference (NCHS/WHO data)

Age (months) As standard deviations

+ 4SD + 2SD Reference ─ 2SD ─ 4SD0 5.0 4.1 3.2 2.3 1.41 6.7 5.4 4.1 2.9 1.72 7.9 6.4 4.9 3.4 1.93 8.9 7.3 5.7 4.0 2.34 9.8 8.1 6.4 4.6 2.85 10.6 8.8 7.0 5.2 3.4

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6 11.3 9.4 7.5 5.7 3.97 12.0 10.0 8.0 6.2 4.48 12.5 10.5 8.5 6.6 4.79 12.9 10.9 8.9 6.9 5.010 13.4 11.3 9.2 7.1 5.311 13.8 11.7 9.6 7.5 5.612 14.2 12.0 9.8 7.8 5.813 14.5 12.3 10.1 8.0 5.914 14.9 12.6 10.3 8.2 6.115 15.1 12.8 10.6 8.4 6.216 15.4 13.1 10.8 8.5 6.317 15.6 13.3 11.0 8.7 6.418 15.8 13.5 11.2 8.8 6.519 16.0 13.7 11.4 8.9 6.620 16.3 13.9 11.5 9.1 6.721 16.7 14.2 11.7 9.2 6.822 17.0 14.4 11.8 9.4 7.023 17.3 14.6 12.0 9.5 7.124 17.8 15.0 12.1 9.7 7.225 18.3 15.4 12.3 9.9 7.326 18.8 15.7 12.5 10.0 7.427 19.2 15.9 12.7 10.2 7.528 19.5 16.2 12.9 10.3 7.629 19.8 16.5 13.1 10.4 7.730 20.1 16.7 13.3 10.5 7.8

Table AP9.1 continued

Age (months)

As standard deviations+ 4SD + 2SD Reference ─ 2SD ─ 4SD

31 20.1 17.0 13.5 10.7 7.932 20.8 12.2 13.6 10.8 8.033 21.1 17.4 13.8 10.9 8.134 21.4 17.7 14.4 11.0 8.135 21.6 17.9 14.2 11.2 8.236 21.9 18.1 14.4 11.3 8.237 22.2 18.4 14.5 11.4 8.338 22.5 18.6 14.7 11.5 8.439 22.7 18.8 14.9 11.7 8.440 23.0 19.0 15.0 11.8 8.541 23.3 19.2 15.2 11.9 8.642 23.6 19.5 15.4 12.0 8.6

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43 23.9 19.7 15.5 12.1 8.744 24.1 19.9 15.7 12.3 8.845 24.3 20.1 15.9 12.4 8.846 24.6 20.3 16.0 12.5 8.947 24.8 20.5 16.2 12.6 9.048 25.1 20.7 16.3 12.7 9.049 25.4 21.0 16.5 12.8 9.150 25.7 21.2 16.6 13.0 9.251 26.0 21.4 16.8 13.1 9.352 26.3 21.6 16.9 13.2 9.453 26.5 21.8 17.1 13.3 9.554 26.8 22.0 17.2 13.4 9.655 27.1 22.2 17.4 13.5 9.756 27.4 22.5 17.6 13.7 9.857 27.7 22.7 17.7 13.8 9.958 28.0 22.9 17.8 13.9 10.059 28.3 23.1 18.0 14.0 10.060 28.6 23.4 18.2 14.1 10.1

Table AP9.5: Weight-for-age (kg) for children aged 5-9.5 years (sexes combined) as standard deviations from reference population (NCHS/WHO data)

Age (years) As standard deviations+ 2SD Reference ─ 2SD

5.0 23.4 18.2 14.15.5 24.8 19.1 14.86.0 26.4 20.1 15.56.5 28.2 21.2 16.27.0 30.2 22.3 17.07.5 32.5 23.6 17.78.0 35.1 25.1 18.58.5 37.9 26.6 19.39.0 41.0 28.3 20.19.5 44.2 30.1 21.0

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Table AP9.6: Height-for-age (cm) for children aged 5-9.5 years (sexes combined) as standard deviations from reference population (NCHS/WHO data)

Age (years) As standard deviations+ 2SD Reference ─ 2SD

5.0 118.2 109.2 100.15.5 121.7 112.3 102.96.0 125.1 115.4 105.66.5 128.5 118.3 108.17.0 131.7 121.1 110.67.5 134.9 123.9 112.98.0 138.1 126.7 115.38.5 141.2 129.4 117.69.0 144.4 132.2 120.09.5 147.6 133.0 122.5

Table AP9.8: Weight-for-age (kg) of children aged 10-18 years (sexes seperate) as standard deviations from reference (NCHS/WHO data)

Age (years) Weight (kg) of Boys Weight (kg) of Girls+ 2SD Mean ─ 2SD + 2SD Mean ─ 2SD

10.0 46.0 31.4 22.1 49.2 32.5 21.910.5 49.3 33.3 23.1 52.8 34.7 23.111.0 52.7 35.3 24.1 56.4 37.0 24.511.5 56.3 37.5 25.4 60.0 39.2 25.912.0 59.9 39.8 26.8 63.3 41.5 27.412.5 63.5 42.3 28.4 66.5 43.8 29.113.0 67.2 45.0 30.4 69.4 46.1 30.813.5 70.9 47.8 32.5 72.1 48.3 32.514.0 74.6 50.8 34.9 74.5 50.3 34.214.5 78.2 53.8 37.4 76.5 52.1 35.915.0 81.6 56.7 39.9 78.3 53.7 37.415.5 84.9 59.5 42.4 79.6 55.0 38.716.0 87.9 62.1 44.7 80.6 55.9 39.816.5 90.7 64.4 46.8 81.2 56.4 40.717.0 93.2 66.3 48.6 81.5 56.7 41.317.5 95.3 67.8 49.9 81.5 56.7 41.818.0 97.0 68.9 50.9 81.3 56.6 42.1

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Table AP9.8: Height-for-age (cm) of children aged 10-18 years (sexes separate) as standard deviations from reference (NCHS/WHO data)

Age (years) Height (cm) of Boys Height (cm) of Girls+ 2SD Reference ─ 2SD + 2SD Reference ─ 2SD

10.0 149.7 137.5 125.3 152.0 138.3 124.610.5 153.1 140.3 127.6 155.3 141.5 127.611.0 156.7 143.3 129.9 158.7 144.8 130.911.5 160.5 146.4 132.2 162.0 148.2 134.412.0 164.7 149.7 134.6 165.2 151.5 137.912.5 168.9 153.0 137.2 168.0 154.6 141.113.0 173.0 156.5 139.9 170.5 157.1 143.813.5 176.9 159.9 142.8 172.4 159.0 145.714.0 180.2 163.1 146.0 173.7 160.4 147.014.5 183.0 166.2 149.4 174.7 161.2 147.815.0 185.1 169.0 152.9 175.3 161.8 148.315.5 186.7 171.5 156.2 175.6 162.1 148.716.0 187.9 173.5 159.2 175.7 162.4 149.116.5 188.8 175.2 161.5 175.8 162.7 149.717.0 189.4 176.2 163.1 175.7 163.1 150.417.5 189.8 176.7 163.7 175.7 163.4 151.118.0 190.0 176.8 163.6 175.6 163.7 151.8

Table AP9.12: Weight-for-height (in kg and cm) for children (49-120 cm; sexes combined) in as standard deviations above and below reference (NCHS/WHO data)

Weight (kg)Height (cm) + 2SD + 1SD Reference ─ 1SD ─ 2SD ─ 3SD49 4.1 3.7 3.2 2.9 2.5 2.250 4.3 3.9 3.4 3.0 2.6 2.351 4.5 4.0 3.5 3.1 2.7 2.352 4.7 4.2 3.7 3.3 2.8 2.453 5.0 4.5 3.9 3.4 2.9 2.454 5.2 4.7 4.1 3.6 3.1 2.655 5.5 4.9 4.3 3.8 3.3 2.856 5.8 5.2 4.6 4.1 3.5 3.057 6.1 5.5 4.8 4.3 3.7 3.258 6.4 5.8 5.1 4.5 3.9 3.359 6.7 6.0 5.3 4.7 4.1 3.560 7.0 6.3 5.6 5.0 4.3 3.761 7.3 6.6 5.9 5.3 4.6 3.962 7.6 6.9 6.2 5.5 4.8 4.163 7.9 7.2 6.5 5.8 5.1 4.464 8.2 7.5 6.7 6.1 5.4 4.765 8.5 7.8 7.0 6.3 5.6 4.966 8.9 8.1 7.3 6.6 5.9 5.267 9.2 8.4 7.6 6.9 6.1 5.468 9.5 8.7 7.9 7.2 6.4 5.769 9.8 9.0 8.2 7.5 6.7 6.070 10.1 9.3 8.5 7.7 6.9 6.271 10.4 9.6 8.7 8.0 7.2 6.472 10.6 9.8 9.0 8.2 7.4 6.6

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73 10.9 10.1 9.2 8.4 7.6 6.874 11.2 10.4 9.5 8.7 7.8 7.075 11.4 10.6 9.7 8.9 8.1 7.276 11.7 10.8 9.9 9.1 8.3 7.477 11.9 11.0 10.1 9.3 8.5 7.678 12.1 11.3 10.4 9.5 8.6 7.779 12.4 11.5 10.6 9.7 8.8 7.980 12.6 11.7 10.8 9.9 9.0 8.181 12.8 11.9 11.0 10.1 9.2 8.382 13.0 12.1 11.2 10.3 9.4 8.583 13.3 12.4 11.4 10.5 9.6 8.784 13.5 12.5 11.5 10.6 9.7 8.885 13.7 12.7 11.7 10.8 9.9 9.086 13.9 12.9 11.9 11.0 10.1 9.287 14.1 15.1 12.1 11.2 10.3 9.488 14.4 13.4 12.4 11.5 10.5 9.6

Table AP9.12 continued

Weight (kg)Height (cm) + 2SD + 1SD Reference ─ 1SD ─ 2SD ─ 3SD89 14.6 13.6 12.6 11.7 10.7 9.890 14.8 13.8 12.8 11.8 10.8 9.991 15.1 14.1 13.0 12.1 11.1 10.292 15.3 14.3 13.2 12.3 11.3 10.493 15.6 14.6 13.5 12.5 11.5 10.594 15.8 14.8 13.7 12.7 11.7 10.795 16.1 15.1 14.0 13.0 11.9 10.996 16.4 15.3 14.2 13.2 12.2 11.297 16.6 15.6 14.5 13.5 12.4 11.498 16.9 15.9 14.8 13.7 12.6 11.699 17.2 16.1 15.0 14.0 12.9 11.9100 17.6 16.5 15.3 14.3 13.2 12.2101 19.0 17.4 15.8 14.4 13.0 11.6102 19.3 17.7 16.1 14.7 13.3 11.9103 19.7 18.1 16.4 15.0 13.5 12.1104 20.0 18.4 16.7 15.2 13.7 12.2105 20.3 18.6 16.9 15.5 14.0 12.6106 20.7 19.0 17.2 15.7 14.2 12.7107 21.1 19.3 17.5 16.0 14.5 13.0108 21.4 19.6 17.8 16.3 14.7 13.2109 21.8 20.0 18.1 16.6 15.0 13.5110 22.2 20.3 18.4 16.8 15.2 13.6111 22.6 20.7 18.8 17.2 15.5 13.9112 23.0 21.1 19.1 17.5 15.8 14.2113 23.4 21.4 19.4 17.8 16.1 14.5114 23.9 21.9 19.8 18.1 16.4 14.7115 24.4 22.3 20.1 18.4 16.7 15.0

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116 24.8 22.7 20.5 18.8 17.0 15.3117 25.4 23.1 20.8 19.1 17.3 15.6118 25.9 23.6 21.2 19.4 17.6 15.8119 26.4 24.0 21.6 19.8 18.0 16.2120 27.0 24.5 22.0 20.2 18.3 16.5

Source : Community nutrition Assessment; JelliffeAnthropometric reference data.

Example: Age of a male person =40 yrs, weight = 50 kg. Evaluate the nutritional status by using WAZ classification. Solution: Age 40 yrs, average weight = 81 kg and SD 13.5 (from the reference value).Calculated WAZ = (50 ― 81.4) ÷ 13.5 = ― 2.325 Comment : Calculated WAZ value is ― 2.325 which is lies between ― 2SD and ― 3SD. This implies that the sample moderately underweight.

Body Mass Index (BMI):

Weight in kg.BMI = ----------------------------- (Height in metre)2

The following cut-off points were used to categories the nutrition status by BMI:

Grade 3 Chronic energy deficiency (CED) ( Severely thinness) :BMI < 16 Grade 2 Chronic energy deficiency (CED) (Moderate thinness) :BMI 16-16.99 Grade 1 Chronic energy deficiency (CED) :17- 18.49 (Mild thinness) BMI 18.5-24.99 : NormalGrade 1 Over weight :BMI 25-29.99 Grade 2 Overweight :BMI 30.00-39.99Grade 3 Over weight :BMI ≥40

(Source: WHO 1995)

Three category of BMIBody Mass Index were usually classified into three categories. The following cut-off points were used to categories chronic energy deficiency (CED), normal and obese:CED = BMI < 18.5Normal = BMI 18.5-24.99Obese = BMI equal or greater than 25

Classification of malnutrition in children aged 1-5 years byMid Upper Arm Circumference (MUAC)

Circumference (cm) Level of nutritionMUAC > 14 NormalMUAC 12.5 – 14.0 Mild / moderate malnutritionMUAC < 12.5 Severe malnutrition

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For Bangladeshi children 11 cm. is the cut-off point.

Classification of adult malnutrition by MUACSex Circumference (cm) Level of nutritionMale MUAC ≥ 23

MUAC < 23NormalMalnourished

Female MUAC ≥ 22MUAC < 22

NormalMalnourished

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