Microsoft Word - AMICS-29Jan2013 - Childinfo.org

The design weights for the households were calculated by multiplying the above factors for each
sample cluster. These weights were then standardized (or normalized), one purpose of which is to
make the weighted sum of the interviewed sample units equal the total sample size at the national
level. Normalization is performed by dividing the aforementioned design weights by the average
design weight at the national level. The average design weight is calculated as the sum of the design
weights divided by the unweighted total. A similar standardization procedure was followed in
obtaining standardized weights for the women s and under-5 s questionnaires. Sample weights were
appended to all data sets and analyses were performed by weighting the data for each household,
woman, or under-5 record with the corresponding sample weights.
A subsample of the households was selected for the AMICS in order to collect data for a hemoglobin
test. In order to reduce the costs of this additional data collection and to facilitate field operations, a
subsample of a 50% households of the AMICS EAs was selected for the test. It was decided to select
an odd number of clusters for the hemoglobin test. This results in a total sample size of 7,740
households in 258 sample EAs. The sample size varies by region from 720 to 960 households, which
should provide a reasonable reliability for anaemia estimates at the regional level. All children under
age 5 and women aged 15-49 in the households of selected clusters were administered a blood test.
The distribution of the subsample EAs and households by region is presented in Table A.2.
Table A.2: Subsample selection for a Hemoglobin Test
Region
Number of EAs and HHs
selected for hemoglobin
test
No. of EAs
No. of Hhs.
Central 53 1,590
Central Highlands 24 720
East 27 810
North 32 960
North East 32 960
South 29 870
South East 29 870
West 32 960
Afghanistan 258 7,740
Since the results are based on a subsample of the EAs selected for the AMICS, the weighting
procedures for the subsample are similar to the overall survey. The only difference is that the term n h
in the formula for the weight refers to the number of sample EAs in stratum h selected for the
hemoglobin test, which is generally one half the number of EAs in the AMICS sample. As a result, the
weights for the subsample households are about twice the corresponding weights for the AMICS
sample households in the same EAs.
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