2014-06-27 All parts are being moved from restricted access to public access.
2011-03-08 All parts are being moved to restricted access and will be available only using the restricted access procedures.
2010-03-04 ICPSR data undergo a confidentiality review and are altered when necessary to limit the risk of disclosure. ICPSR also routinely creates ready-to-go data files along with setups in the major statistical software formats as well as standard codebooks to accompany the data. In addition to these procedures, ICPSR performed the following processing steps for this data collection:
- Performed consistency checks.
- Created variable labels and/or value labels.
- Checked for undocumented or out-of-range codes.