1988-01-06 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:
- Checked for undocumented or out-of-range codes.
2005-11-04 On 2005-03-14 new files were added to one
or more datasets. These files included additional setup files as well
as one or more of the following: SAS program, SAS transport, SPSS portable,
and Stata system files. The metadata record was revised 2005-11-04 to
reflect these additions.
2006-03-30 File CB8704.ALL.PDF was removed from any previous datasets and flagged as a study-level file, so that it will accompany all downloads.
1998-06-12 The data have been reformatted. SAS and SPSS data
definition statements have been prepared, and a machine-readable
codebook and data collection instruments are now available as a
Portable Document Format file.