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A Nutrition Baseline Survey is undertaken in
five mains steps:
Step 1: Collection of available information on the nutritional situation
of the population and other demographic, socio-economic, ecological
and cultural data in the survey region
- Revise the scientific literature, such as:
a) Medical / nutrition data banks, journals etc.,
b) Published data form national or international institutions. For
specific country profiles see: www.unicef.org; www.who.org,
www.worldbank.org, www.fao.org,
c) Ministries in the country,
d) Homepages of GTZ projects (e.g. Ifsp-srilanka.net).
- Obtain nutritional information directly in the local setting through
observational techniques or group discussions.
Step 2: Planning and preparation of the Survey
- Discuss general considerations on survey design, surveyed groups
and objectives.
a) A simple cross-sectional design is often used for Nutrition
Baseline Surveys.
b) The specific objectives of your particular survey should be
determined and depend on the project’s assumptions.
- Organize your survey Team.
- Conducting a Nutrition Baseline Survey is not a one-person job.
Generally, the survey team consists of:
a) A survey coordinator, task: for the general responsibility of
the design, methodology, training and application/ analysis
of the survey,
b) Members of the project, for the design of the survey’s
objectives and contents,
c) A statistician or data analyst, for data entry and statistical
analysis of the obtained data,
d) Surveyors, who are in direct contact with the surveyed
population, for the systematic collection of data during
the survey,
e) Supervisors, for the support of the surveyors in the field to
guarantee the quality of the survey (each supervisor has 2-5
teams), and
f) Some advisors, for appropriate consultation, e.g. community
leaders, extension workers from the ministries, community
health workers.
a) Integrate the persons who will be responsible for nutrition and
public health during later project implementation. This assures
a good field entrance and establishes a continuity of the rela-
tionship with the community.
b) When all survey steps are prepared, train the whole survey
team for a few days in the methodology, questionnaires and
communication techniques to be applied in the field.
- Design the sampling procedures.
a) Sampling is the procedure of selecting a representative part of
the population. The results obtained from the persons in the
sample reflect the characteristics of the entire population being
studied.
b) Generally, a simple random sampling or a two-stage-cluster
sampling is used for Nutrition Baseline Surveys.
c) The sample size is a compromise between the ideal size to be
statistically representative and the realistic size based on the
given resources in terms of money and time.
- Design the questionnaires.
Each survey needs its own particular questionnaire. There are
three different types of questionnaires to be distinguished:
a) Socio-economic household data questionnaire
(Possible areas or variables are occupation, formal education,
family income, housing conditions, basic infrastructure or
dietary pattern and food habits on family level such as number
of meals, frequency of intake of particular food items.)
b) Individual data questionnaire
(Possible areas or variables are type of weaning food,
breastfeeding practices, anthropometric measurements
(weight, height, sex, age etc.), episodes of infectious diseases.)
c) Community-specific data sheet containing information on
health services, types of schools, electricity supply, climate, food
shortages and agricultural production, community-based
organisation etc. at village or district level.
- Pre-test the questionnaires.
a) A pre-test should be carried out in the field. Each location has its
culturally determined language and forms of communication.
Formulate the right questions and pre-formulate the specific
answer categories.
b) A pre-test in a small sample (around 20 –30 households) is
sufficient to adjust the questionnaire adequately and to avoid
systematic errors.
c) After the revision of questions and length according to the pretest
results, the questionnaire can be finalized, pre-numbered
and printed for distribution.
- Check if the following resources needed to conduct a Nutrition
Baseline Survey are available:
a) Personnel - Survey coordinator, supervisor, surveyors, driver,
persons for data entry.
b) Means of transportatio - cars, public transport.
c) Equipment and supplies (for interviews: maps, materials such
as pens and pencils, reproduced questionnaires; for anthropometric
measurements: weighing scales, anthropometer,
measuring tapes, MUAC (=Mid-upper-arm-circumference tapes);
for data processing: computer, software programmes, diskettes,
paper).
Step 3: Implementation of the Survey
- Introduction of the survey in the communities
a) Before starting the field work, the survey coordinator and the
supervisors should visit the survey region and meet with the local
government officers and the community leaders to introduce the
survey team and to explain the survey’s objectives.
b) It is recommended to prepare a simple written statement for the
interviewers, to show to the local authorities or anyone interested,
about the purposes of the survey and where it takes place.
- Application of the questionnaire
a) The success of the survey questionnaire rests in the hands of the
interviewers. They should be able to speak the local language, to
ask questions in an organised way, to record and measure
adequately and be unbiased in asking (sensitive) questions.
b) The surveyors should use certain communication techniques to
establish a relationship of trust during the interviews, encouraging
the respondent to talk freely and openly on the survey topic.
c) A surveyor can complete a maximum of 5-6 interviews per day,
including measurements of weight and height and the time spent
to locate the households. It is recommended that a team of two
surveyors visit a household to support each other.
d) Each applied questionnaire requires a careful review after the
interview to check its completion and accurate codification.
Questions and mistakes in the editing or recording should be
discussed with the supervisor in the field at the end of the day.
Each supervisor is responsible for approximately 4-5 surveyor
teams and manages the data control together with the survey
coordinator.
e) The questionnaires should be kept clean and dry for data entry
and processing in the office.
- Anthropometric measurements
a) Body measurements of children and/or adults (Anthropometry)
are international standard practices for assessing the nutritional
situation within a population. If precise information about the
weight or height is available and the age of the person is known,
nutritional indices can be calculated to establish categories of
malnutrition for each sex group.
b) How to measure and weigh children (see: United Nations, 1986.)
c) The most common types of indicators of malnutrition
(see: WHO, 1995.*)
- Observation of the household conditions
a) During the whole survey, the surveyors should observe the living
and housing conditions of the interviewed families, in order to
cross check what they see and what the respondents say.
b) Interviewers should be sensitive and aware of anything during the
visits of the households for further data interpretation.
Step 4: Data processing and analysis
Specific software-programs have been developed to process nutritional
and anthropometric data easily. An example can be found at:
www.cdc.gov/Epi-Info; www.nutrisurvey.de
Apart from the software selected for data processing, the analysis of the
data should be done in different stages:
The questions have numerical codes or categories and can be easily
entered into the standardised data entry section of EPI-Info. The
pre-coded questionnaires can be translated into data entry files,
which include all variables of the questions, as well as the
anthropometrical information. The household number should be on
each questionnaire so that the individual files (of the children) can be
merged with the corresponding household file.
- Validity and plausibility checks
Inconsistencies in the data within the questionnaire, unreasonable
and impossible entries can be avoided using the EPI-Info plausibility
check. Normal ranges can be established (e.g. the amount of food
physiologically tolerable, the age range of the measured children
between 0 and 5 years) to reduce erroneous data during data entry.
Another plausibility procedure is to cross check the data from the
household and individual questionnaire, e.g. the age of a child must
be the same in the individual and household register form.
- Anthropometric calculation
Anthropometric indices are calculated automatically by entering the sex,
age, weight and height of the child. To determine the nutritional status
of children under 5 years, the following indices are internationally
practiced:
a) Weight-for-Age (W/A)
b) Height-for-Age (H/A)
c) Weight-for-Height (W/H)
The EPI-Info Program calculates the percentages of the population with
anthropometric index below –2 z-scores and above – 2 z-scores of the
NCHS reference population. These cut-off points classify malnourished,
normal and overnourished population groups. (see: WHO, 1995.)
- Clustering for descriptive analysis
In order to interpret the nutritional status (W/H, W/A, H/A) which is
the dependent variable for any statistical test, specific clusters or groups should be classified by logical or statistical relationships.
The following examples show some useful relationships:
a) Comparison of the nutritional status of children exclusively
breastfed with those who got only bottle feeding.
b) Comparison of the nutritional status of children, which show a
balanced food intake, or an adequate composition of the weaning
food.
c) Comparison of the nutritional status of the children with good
drinking water facilities at the household level.
d) Comparison of the nutritional status of the children whose mothers
have good nutritional knowledge and practices.
Formulate the hypothesis on the basis of the list of questions and variables which could influence on the nutritional status. Describe any
variable for the corresponding population group by age, sex, region,
ethnic origin etc.
- Detailed in-depth analysis of causes and determinants of malnutrition
Use an advanced statistic software program (e.g. SPSS) in order to
determine the causes of malnutrition.
Step 5: Dissemination of the results and preparation for translation into action
- Provide the necessary information on the nutritional situation of
the target population of the project before critical discussions and
decisions concerning project interventions have been made.
- The final report should also be easy to read, well-structured and
understandable in order to be a usable working instrument
during project implementation.
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