Primary Sampling Unit | Based on proportional population to size (PPS) sampling, each of the 21 clusters was selected from 137 Khoroos (suburbs) in urban and 324 Soums (regions) in rural areas respectively; |
Secondary Sampling Unit | For each Khoroo and Soum, 2 family centres (groups of ± 1000 households) and Baghs (sub-regions) were selected respectively using PPS; |
Tertiary Sampling Unit | Based on the list of households from the selected secondary sampling units, 82-84 households were selected using simple random sampling to make a final sample; |
Participants | One person aged 15-64 years in the selected household was selected at random. These were selected at random using a predefined, paper-based algorithm. |