Sampling Frame
From ICE Primer: A Tobacco Control Research Methodology Primer
A sampling frame for a survey is a list or map from which population members can be selected for the sample.
Household surveys
For large or medium scale health surveys, the sampling design is typically a stratified multistage sample, and the conceptual frame is typically a frame of dwelling units or residences. A household is thought of as the collection of people living in a dwelling unit.
The strata often correspond to geographic areas which are either administratively convenient to sample separately, or thought to be homogeneous with respect to characteristics of interest.
Area frames of households
Within strata, the population of households may be mapped using an area frame, constructed in stages. At the first stage of an area sampling scheme, the population of households may be divided into primary sampling units, or PSUs, determined by geographic boundaries. They may correspond to census districts, electoral districts, or the first few digits of postal codes. Once a sample of PSUs is drawn, the sub-frame for each sampled PSU may be constructed, either by listing households, or by dividing the map areally into smaller secondary sampling units. Those secondary sampling units which are chosen may in turn be listed or mapped.
Telephone frames of households
When the survey is to be conducted by telephone, the strata may correspond to regions, perhaps defined by area codes, or to communities within regions. The sampling frames could be telephone directories, or could consist of banks of randomly generated telephone numbers.
For example, the method of listed 100-bank sampling is carried out as follows. Define a "100-bank" to consist of all numbers with a given area code and first five digits, e.g. the 100 numbers of form 519-886-43xy. From an electronic list of listed numbers, determine all 100-banks (within a given stratum) that have at least one listed residential number. Then take a random sample of numbers from this collection of 100-banks.
