ABC News/BBC/ARD Afghanistan Poll – Note on Methodology
National Afghanistan survey involved a random sample of 1,534 Afghan adults
Jan. 11, 2010 —
This survey was conducted for ABC News, the BBC and ARD by the Afghan Center for Socio-Economic and Opinion Research (ACSOR) in Kabul, a subsidiary of D3 Systems Inc. in Vienna, VA, USA. Interviews were conducted in person, in Dari or Pashto, among a random national sample of 1,534 Afghan adults Dec. 11-23, 2009.
A total of 194 sampling points were distributed proportional to population size in each of Afghanistan's 34 provinces, stratified by urban/nonurban status. Sampling points were then distributed to randomly selected districts within provinces, also proportionate to population size; and lastly to randomly selected villages or neighborhoods within those districts, by simple random sampling. Sources for population parameters were population projections from the Afghan Central Statistics Office.
Half the sampling points were designated for male interviews, half for female interviews. Male respondents were interviewed only by male interviewers, female respondents only by female interviewers. Residences were selected within each settlement by random route/random interval and respondents were selected within residence by Kish grid.
In addition to the national sample, oversamples were drawn in Balkh, Helmand, Herat, Kandahar, Kunduz, Logar, Nangarhar and Wardak provinces to allow for more reliable analysis in those areas. The sample was weighted by population of province and sex by region.
In order to reduce the design effect due to clustering, where randomly drawn male/female sampling points fell within close proximity to each other in districts with fewer than 20,000 residents, the number of sampling points was doubled, also by random selection, and the number of interviews per point was halved, from 10 to 5. Of the total of 194 sampling points, 80 were assigned in this manner.
Of the 101 districts initially drawn in the sample, 11 were inaccessible for security reasons and were randomly replaced with other districts in the same province; a 12th was inaccessible because a road washed out, and likewise was replaced. At the settlement level, 21 of the 194 sampling points were replaced for various accessibility reasons, a customary number of settlement-level replacements. These were randomly substituted with settlements in the same districts. In three sparsely populated provinces, Paktika, Uruzgan and Zabul, female interviewers could not work, so women couldn't be interviewed. These provinces account for 1.7, 1.3 and 1.2 percent of the country's population, respectively.
Interviews, which averaged 32 minutes in length, were conducted by 168 interviewers (81 female and 87 male) in 34 supervised teams. All interviewers were trained and all had experience on previous ACSOR field projects. Ten percent of interviews were directly observed by field supervisors, 18 percent were back-checked in person afterwards, and an additional 3 percent were checked from the ACSOR's central office. Questionnaires were all subjected to logical controls conducted at ACSOR offices in Kabul.
The survey had a contact rate of 89 percent and a cooperation rate of 97 percent for a net response rate of 86 percent. The impact of clustering on the sample produces an estimated design effect of 1.46, for a total margin of sampling error of 3 percentage points at the 95 percent confidence level.