Sample frame describes the sampling frame used for identifying the population from which the sample was taken. For example, a telephone book may be a sample frame for a phone survey. In addition to the name, label and text describing the sample frame, this structure lists who maintains the sample frame, the period for which it is valid, a use statement, the universe covered, the type of unit contained in the frame as well as the number of units available, the reference period of the frame and procedures used to update the frame. Use multiple use statements to provide different uses under different conditions. Repeat elements within the use statement to support multiple languages.