Food consumption analysis

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Food consumption analysis

5 th - 9 th December 2011, Rome

Contents

Food consumption score (FCS)

Explore the questionnaire module

Calculate

Create the FC groups

Dietary diversity (DD)

Explore the questionnaire module

Calculate

 Validate the indicators

 Present the outputs

Definitions

Dietary diversity

Food frequency

Household Food

Consumption

The number of individual foods or food groups consumed over a reference period (7 days, 24 hours)

Number of days (in the past week) that a specific food item has been consumed by a household

The consumption patterns (frequency *

diversity) of households over the last seven days

The FOOD CONSUMPTION SCORE

(FCS)

Food consumption module

Food consumption module continued

Information:

 Weekly frequency of foods and/or food groups

Sources of foods

Numbers of meals

Indicators:

→ FCS

DD– dietary diversity

Food and Food group frequency (0-7)

Average number of meals (children/adults)

Sources of food

Food consumption score - FCS

The Food Consumption Score is a composite score based on dietary diversity , food frequency and relative nutrition importance of different food groups.

Data collection

 The data have to be collected according to usual food items consumed that are specific to the country’s context.

 Food items are grouped into food groups that are standard.

 The difference between foods and condiments must be captured during the data collection.

Calculation steps

1.

2.

3.

4.

5.

Using standard 7-day food frequency data, group all the food items into specific food groups.

Sum all the consumption frequencies of food items of the same group , and recode the value of each group above 7 as 7.

Multiply the value obtained for each food group by its weight and create new weighted food group scores.

Sum the weighed food group scores, thus creating the food consumption score (FCS).

Using the appropriate thresholds , recode the variable food consumption score, from a continuous variable to a categorical variable, to create the food consumption groups.

FCS

FCS = a staple x staple

+ a pulse x pulse

+ a veg x veg

+ a fruit x fruit

+ a animal x animal

+ a sugar x sugar

+ a dairy x dairy

+ a oil x oil

FCS x i a i

Where,

Food consumption score

Frequencies of food consumption = number of days for which each food group was consumed during the past 7 days

(7 days was designated as the maximum value of the sum of the frequencies of the different food items belonging to the same food group)

Weight of each food group

Food groups and weights

FOOD ITEMS

1

Maize , maize porridge, rice, sorghum, millet pasta, bread and other cereals

2 Cassava, potatoes and sweet potatoes

3 Beans. Peas, groundnuts and cashew nuts

4 Vegetables and leaves

5 Fruits

6 Beef, goat, poultry, pork, eggs and fish

7 Milk yogurt and other diary

8 Sugar and sugar products

9 Oils, fats and butter

10 Condiments

Food groups

Cereals and

Tubers

Pulses

Vegetables

Fruit

Meat and fish

Milk

Sugar

Oil

Condiments

Weight

2

1

4

3

1

4

0.5

0.5

0

 The score as a minimum of 0 and a maximum of 112.

 Can be presented as mean or can be recoded into food consumption groups

FCS thresholds

Once the FCS is calculated, the thresholds for the FC

Groups (FCG) should be determined based on the frequency of the scores and the knowledge of the consumption behaviour in that country/region.

The typical thresholds are:

Threshold

0 – 21

21.5 - 35

>35.5

Profiles

Poor food consumption

Borderline food consumption

Acceptable food consumption

Thresholds with oil and sugar eaten on a daily basis

(~7 days per week)

0-28

28.5 - 42

>42.5

Why 21 and 35?

A score of 21 was set as barely minimum, scoring below 21, a household is expected NOT to eat at least staple and vegetables on a daily base and therefore considered to have poor food consumption. Between 21 and 35, households are assessed having borderline food consumption.

The value 21 comes from an expected daily consumption of staple and vegetables.

» frequency * weight, (7 * 2 = 14)+(7 * 1 = 7).

The value 35 comes from an expected daily consumption of staple and vegetables complemented by a frequent (4 day/week) consumption of oil and pulses.

» (staple*weight + vegetables*weight + oil*weight + pulses*weight =

7*2+7*1+4*0.5+4*3=35).

……Even though these thresholds are standardized there is always room for adjustments based on evidence……

How to adapt the thresholds

1.

2.

3.

Consider the basic/minimum food consumption in the country.

Ex. Laos diet is mainly rice and vegetables, but in some country you can have oil and/or sugar consumed daily

Based on the data information and the knowledge of the country try to define the thresholds for poor and borderline consumption.

The thresholds should be changed based on evidence and should be remain the same if you want to compare

FCS of different surveys.

Example

Examples of different thresholds:

 Sudan

 Two different thresholds were used for North and South Sudan

 Haiti

 26 & 46 were used because the consumption of oil and sugar among the poorest consumption were about 5 days per week.

!!!! We have to be careful that changes from the standard are very well justified and reported otherwise we can be viewed as changing the threshold ‘ to get the numbers we want’ !!!!

DIETARY DIVERSITY analysis (DD)

Dietary Diversity definition

The number of individual foods or food groups consumed over a reference period (7 days, 24 hours).

Dietary Diversity Score

There are different scores on based on:

 Level

 Individual (women or children) vs Household score

 Recall

 7 days vs 24 hrs

 Different numbers of food groups ( 7 to 16)

Different DD scores

Score

HDDS – household 16 food groups

FAO

IFPRI

IDDS – women or children 16 food groups

DDS

7 food groups

Groups

-

-

6+ : high

4.5-6 : medium

<4.5 : low

Calculation steps

1.

2.

3.

Group all the food items into specific food groups if necessary.

For each food group create a new binominal variable that has 1 (yes) if the household/ individual consumed that specific food group or 0 (no) if the food did not consume that food.

Sum all the food groups variables in order to create the dd score. The new variable will have 0 as minimum and as maximum the total number of food groups collected (7 to 16).

Dietary Diversity Score

DD = ∑ P i

DD

P i

Where, dietary diversity score

1 if the food group was consumed, 0 if it was not consumed

Validation of the indicators

Validation of the FCS

Run verifications of the FCS, FCGs DD DD groups by comparing them to other proxy indicators of food consumption, food access, and food security for example:

 Cash expenditures,

 % expenditures on food,

 food sources,

 CSI,

 wealth index,

 number of meals eaten per day, etc.

Correlations

Correlations with FCS comparing FCS to other food security proxies

Burundi

Pearson Correlation 0.31 kcal/capita/day

Sig. (2-tailed)

Pearson Correlation

<0.01

-0.27

CSI score

Sig. (2-tailed) <0.01

% total cash expenditures on food

Pearson Correlation -0.11 asset index

Sig. (2-tailed)

Pearson Correlation

Sig. (2-tailed)

<0.01

0.24

<0.01 total cash monthly expenditures (LOG)

Pearson Correlation 0.28

<0.01

CSI score

No. of assets

No. of means (adults)

Total per cap. Cash exp. (LOG)

Sig. (2-tailed)

Malawi

Pearson Correlation

Sig. (2-tailed)

Pearson Correlation

Sig. (2-tailed)

Pearson Correlation

Sig. (2-tailed)

Pearson Correlation

Sig. (2-tailed)

-0.30

<0.01

0.40

<0.01

0.33

<0.01

0.31

<0.01

We use correlation when we analyse 2 scale/continuous variables ex.

 FCS with DD

 FCS with Kcal

 DD with asset index

Compare means

North

Central

South

FCS

45

38

27

DD

6.7

5.1

4.2

Poor FC

Borderline FC

Good FC

Age household head

36

45

42

 We use compare mean when we analyse a scale/continuous variable with a categorical/ nominal one.

 ex.

 FCS by urban/rural

 FCGs by age household head

PRESENT the RESULTS

Graph

Laos FCS

Staple

Sugar

Vegetables

Fruit

Anim protein

Pulses

Oil

Milk

49

42

35

28

21

14

7

-

15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90

FCS

 This graph aids in the interpretation and description of both dietary habits and in determining cut-offs for food consumption groups (FCGs).

Graph continued

consumed (*)

(Days/week)

7.00

6.00

5.00

Staple

Fruit

Anim protein

Oil

Pulses

Sugar

4.00

3.00

2.00

1.00

-

0 10 20

(*) w eighted moving average over 7 point range

30 40 50 60

Food Consumption Score

70 80

Vegetables

Milk

90 100

This graph shows the consumption frequency of different food groups by FCS independently and not stacked as the previous graph.

How to create the graph

4.

5.

1.

2.

3.

6.

Truncate the FCS variable

Run a frequency of the FCS

Run a compare mean of the FCS and all the food groups included in the FCS

Export frequency and compare mean in excel

Calculate an average of the surrounding values for each food group (to smooth the graph).

Use the ‘area’ or the ‘line’ graph in excel.

100%

90%

80%

70%

60%

50%

40%

30%

20%

10%

0%

1 2 3 4 quintiles de indice de richesse

5

acceptable limite pouvre

acceptable limite pauvre

0 7

Maize

Other Cereals

Beans, Peas

Fruits

Fish

Milk/Yoghurt

Sugar, Honey, Jam

14 21 28 35 42

Rice

Casssava, Sweet Pots, Bananas

Vegetables

Meats

Eggs

Oils/Fat/Butter

49

Poor and Borderline FCG

35%

30%

25%

20%

81

71

81 80 82 77

83 86

78 80 81

84

77

69

77

83

91 89

81

15%

10%

5%

0%

D ah

S uk

N in ul ay aw a m an iy ah

Ta m ee m

E rb il

D ia la

A nb

B ar ag hd ad

B ab il

K ar ba la

W

S as si t al ah

A l D in poor borderline

N aj af

Q ad is si a

M ut ha na

Th i –

Q ar

M is sa n

B as ra h

To ta l

Mean

30

20

10

0

100

90

80

70

60

50

40

food consumption score

CSI wealth index per capita total expenditure per capita non foof expenditure total_Income

Spearman's rho

Correlation Coefficient

Sig. (2-tailed)

N

Correlation Coefficient

Sig. (2-tailed)

N

Correlation Coefficient

Sig. (2-tailed)

N

Correlation Coefficient

Sig. (2-tailed)

N

Correlation Coefficient

Sig. (2-tailed)

N

Correlation Coefficient

Sig. (2-tailed)

N

food consumption score

1

.

24975

-.111(**)

0

8877

.378(**)

0

24972

.406(**)

0

24971

.343(**)

0

24971

.430(**)

0

24934

Food Sources

Sources of food

We have information about source of single food but we need an indication of sources of all the food items consumed in the households.

This indicator can be used as proxy of food access.

( ex. dependency on market, food assistance or own production)

Sources of food

Transform the single sources (x variables as the food items) into n variables as the different sources of food;

Own production, purchase, food assistance, borrow, exchange, gathering, social network, etc.

Doing this we will have the percentage of food consumed coming from different sources

Ex % coming from purchase and % from food aid etc.

In this computation the sources of food should be weighted on the frequency of the food items consumed.

Steps

1.

Copy the food frequency value into new variable called as the different sources.

IF (source_rice =1) ownproduction_rice =consumption_rice.

IF (source_rice =2) purchase_rice = consumption_rice.

IF (source_rice =3) foodaid_rice = consumption_rice .

IF (source_rice =4) gathering_rice = consumption_rice.

IF (source_rice =5) borrowrice = consumption_rice . execute.

Do this computation for all the food items and all the sources.

Steps

2.

Add all the variables of different foods with the same sources together in order to create the unique variable of the specific source

COMPUTE ownproduction = ownproduction_rice + ownproduction_tubers + ownproduction_eggs + ownproduction_vegetable + ownproduction_meat + ownproduction_fruit + ……

3.

COMPUTE the total sources of food totsource = ownproduction + fishing + purchase + traded + borrow + exc_labor + exc_item + gift + food_aid +other.

4.

Calculate the % of each food source

COMPUTE pownprod = (ownproduction / totsource)*100.

COMPUTE pfishing = (fishing / totsource)*100.

COMPUTE ppurchase = (purchase / totsource)*100.

COMPUTE pborrow = (borrow / totsource)*100.

COMPUTE pexclabor = (exc_labor / totsource)*100.

COMPUTE pexcitem = (exc_item / totsource)*100.

COMPUTE pfoodaid = (food_aid / totsource)*100.

COMPUTE pother = (other / totsource)*100.

Sources of PDS food basket

100%

80%

60%

40%

20%

64

40

33

47

39

62

52

41

67

54

63

48

66

70

60

58

49

16

0%

D ah uk av a

N in

Su la ym an iy ah

Ta m ee m ppds_pds

Er bi l

D ia la

An ba r

Ba gh da d ppds_purchase

Ba bi l

Ka rb al a

W as si t

Sa la h

A l D in

N aj af

Q ad is si a

M ut ha na

Th i –

Q ar ppds_ownproduction ppds_family

M is sa n

Ba sr ah

OTHER

To ta l

49

Sources of all foods

100%

90%

80%

70%

60%

50%

40%

30%

20%

10%

30

19

16

22

0%

D ah uk aw a

N in

Su la ym an iy ah

Ta m ee m

Er bi l

17

D ia la

8

28

An ba r

Ba gh da d

21

15

29

24

Ba bi l

Ka rb al a

W as si t la h

A

Sa l D in

28

21

32 34

26

24

N aj af

Q ad is si a

M ut ha na

Th i –

Q ar

M is sa n

Ba sr ah

17

To ta l

21 p_pds p_purchase p_ow nproduction p_family other

Food sources - rural model

Plains

Coastal

Tonle Sap

Total

Plateau

0% 20% 40% 60% type of source

80%

% own producion % fishing and hunting

% purchased+traded % other

100%

Food sources - urban model

Phnom Penh

Coastal

Total

Plains

Tonle Sap

Plateau

0% 20% 40% 60% type of source

80% 100%

% own producion % fishing and hunting

% purchased+traded % other

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