Data Export Files

August 18, 2016


The exported data will be in a .zip file containing one or more files. The number of such files is a function of the structure of the questionnaire, meaning that exporting produces one file per level of observation in the questionnaire, or in other words in addition to one file at the questionnaire level, each roster in the questionnaire will generate another export file.  For example, one file for household-level variables, one file for household member-level variables, and one file for asset-level or consumption item-level variables. Additionally, the .zip file will contain interview comments and interview actions files.  

Note that the exported data differentiates between missing values caused by the logic of the questionnaire (skipped questions) and missing values due to absence of an answer. Only the values of the logically skipped questions will be have missing values (blanks in tab-delimited files), whereas -999999999 or  ##N/A## (for string variables) will be exported whenever an answer to a question was expected, but not recorded for string variables).

Data formats

The actual files exported will differ slightly based on the file format you have chosen to use.
Tab** **

  • Exports tab-delimited data in .tab files
  • Each file is accompanied by a Stata .do file that reads the .tab file into memory, and applies variable and value labels


  • Exports DTA files directly. If .do file for applying variable and value labels desired, they can be found accompanying the tab-delimited data. 
  • Version 14, which supports Unicode standard for string data. 


  • Exports SAV file directly. 

DDI** **

  • If you are thinking about committing your collected data into a public repository you are likely to be requested for a DDI description of your data. 
  • Data Documentation Initiativeis an international project to create a standard for meta data in social sciences. You can export an xml file with meta information about your data for processing in DDI compatible software, for example Nesstar Publisher 
  • The following information is exported: the list of data files, variables, their types, labels, question texts, interviewer instructions, etc.

**How the questionnaire structure affects the number of export files **

We will now explain how the data files are exported through an extended example. In Questionnaire Designer, the example survey (below) consists of questions about the interview at the household level and a household roster that include questions about each household member. 


Data collected using this questionnaire is exported in the following number of files: One file at the questionnaire/household level of observation, another file at the household members/parent level, and two system generated service files on interview actions and comments. 

Click the relevant links to see more detailed information regarding the anatomy of each file: Questionnaire (both questionnaire and parent level files), System Generated