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Figure 2.1 Implementation of NRVA 2011-12 sampling clusters, by district
The principle of double data entry was introduced to avoid high levels of manual data capture errors. For each of the double-entered batches integrity checks were performed at individual, household and batch level. Emerging issues were
resolved by a team of seven data editors. A complementary MS Access programme identiied discrepancies between the batches of double-entered data, which were subsequently reconciled and again tested for integrity.
Further data editing was irst performed on the MS Access database. This database was then transferred to Stata software for the application of programmes to identify data laws and either perform automatic imputation or manual
screen editing. Data processing was completed in September 2012. During the analysis phase, inal edits were done.
2.9 Comparability of results
Comparability between the 2007-08 and 2011-12 surveys was maintained as much as possible by a largely similar questionnaire design and content for reported indicators, training and data collection procedures. Whereas the
sampling design differed between surveys, both surveys produced representative results at national and provincial level. Comparability with NRVA 2005 is more limited due to major questionnaire revisions in 2007 and the limitation of
data collection to three months in 2005, which prevented seasonal analysis like that in the last two NRVA rounds. Any comparison with 2005 results in this report should, therefore, be treated with caution.
7
The NRVA questionnaire design partially built on major international survey practices, such as the DHS and MICS surveys. In addition, for internationally agreed indicators, NRVA usually applies the standard conceptualisation and
deinitions. Therefore, many indicators produced in this report embody a high level of international comparability. The report text indicates if, for some reason, applied deinitions deviate from the internationally recommended ones. The
annex with concepts and deinitions provides the speciications applied in the present analysis Annex XI.
7 As sampling design, survey design and questionnaire content of NRVA 2003 were very different from the subsequent rounds, no effort is made here to include its results in any trend analysis.
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SURVEY METHODOLOGY AND OPERATIONS
2.10 Data limitations
The speciic constraints in the Afghanistan context in terms of security problems, cultural barriers and local survey capacity induced some data limitations. The following observations should be taken into account when interpreting the
results in this report: • In 150 out of 2,100 cases 7.1 percent, originally sampled clusters could not be visited, in most cases due to security
reasons. For 133 of these cases 6.3 percent of the total, clusters were replaced. As the non-visited areas may have proiles different from visited areas, the inal sample will have a slight bias in the results. This effect will have been
larger at the provincial level for provinces with relatively large numbers of replacement. • In 18 percent of the cases, sampled areas were temporarily inaccessible due to insecurity 13 percent or physical
access problems 5 percent, concentrated in winter time. Upon improvement of local conditions these areas were covered in a later round of data collection.
• Out of the 21,000 household interviews scheduled, 20,828 99.2 percent were actually implemented. This data reduction is limited and has not signiicantly affected the reliability of data.
• Analysis of the population structure by sex and age shows under-enumeration of women and girls, and young children, especially infants. Coverage of the youngest age group was much better than in 2007-08, but signiicant
numbers are still omitted. Cultural backgrounds related to the seclusion of women and high infant mortality are among likely reasons for these omissions.
• Although an improvement compared to NRVA 2007-08 can be noted, the quality of age reporting in the Afghan population remains very poor, as indicated by large age heaping on ages with digits ending on 5 and 0.
8
• Due to security problems, work by female interviewers in Zabul was very restricted. Consequently, the information on maternal and child health, and fertility and mortality information is largely missing for this province. However, the food
consumption module in the female questionnaire was collected by male interviewers interviewing male respondents.
2.11 Reporting
The source of all information presented in this report is the NRVA 2011-12, unless otherwise speciied. Presenting information from other sources than NRVA does not imply an endorsement by CSO, but should merely be interpreted as
a contextualisation of the present indings. Titles of tables presented in this report follow a standard convention to exactly deine the table contents and structure:
irst, the title states the universe of elements presented in the table, then it deines the variables presented in the column headings, then the variables presented in the row headings. In the title the universe and the column variables
are separated by a comma ‘,’; the column variables and the row variables are separated by ‘, and by’.
8 The Myers Blended Index is 20.6 and the Whipples Index is 223.
