2006-03-30 File CB6850.ALL.PDF was removed from any previous datasets and flagged as a study-level file, so that it will accompany all downloads.
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.
2001-02-16 A correction was made to the formula for
calculating the Coverage Indicator listed in the ICPSR Data Collection
Description section of the codebook.
1997-05-30 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:
- Standardized missing values.
- Performed recodes and/or calculated derived variables.
- Checked for undocumented or out-of-range codes.