Monday, March 22, 2010

Survey of Income and Program Participation (SIPP): Core Questions on Disability

In an exploration of Census Bureau statistics on disabilities, I wanted to examine the questions that were asked in the most recent panel of the Survey of Income and Program Participation (SIPP).  A SIPP Data page at the website of the National Bureau of Economic Research (NBER) seemed to indicate that results from the 2008 panel were only starting to come out.  Similarly, at the Bureau's own SIPP website, a 2008 Panel SIPP Data Product Schedule indicated that, as of March 2010, Waves 1-4 of the 2008 Panel were to have been completed, but only the Wave 1 data were actually supposed to be available.

The Census Bureau indicates that the SIPP consists of core content plus topical modules.  At present, the most recent core content shown on the Bureau's Core Content webpage is that of the 2004 Panel.  That is, the 2008 questionnaire did not appear there; this seemed to be one of several Bureau webpages that seemed not to be maintained currently.  I went back to that NBER webpage, went down to the 2008 Panel listings, and saw that there was not yet a PDF file listed on the 2008 Wave 1 Core row.  I took a look into the file listed next to it, but when I unzipped it I saw that it contained only a .dat file suitable for opening in a statistics program like SPSS.

I went looking for the 2008 Panel questionnaire.  On the Bureau's SIPP User Guide webpage, I found this statement:

We are currently updating the Third Edition, 2001. The revised chapters include information on the 2001 Panel, 2004 Panel and current up-to-date information on the 2008 Panel. All chapters are currently being revised.
I opened the SIPP Users' Guide, Third Edition, 2001 PDF.  It seemed to contain a lot of useful information, but not an actual copy of any questionnaires.  This was not surprising; the 2004 questionnaires, with instructions and all, had been several hundred pages long.  I found another page, described as the SIPP FTP page, and it offered several files related to the 2008 Panel -- some data files, and also some technical text files -- but no copies of the 2008 questionnaire.  I found the reason in a footnote (p. 16, n. 11) to a Census Bureau Research Report by Moore et al. (2009), "The 2008 Survey of Income and Program Participation Event History Calendar Field Test:  Study Design and Initial Results."  That footnote referred to the "automated" SIPP questionnaire.  This explained the odd format I had seen in the 2004 questionnaires:  they had apparently been attempting to replicate, on paper, the different decisions that a computer program would make, regarding which questions to ask next, based on what the respondent said.

Revising my search, I found a reference to AttA - W1 Core Items Booklet.pdf in a webpage., apparently maintained by the Regulatory Information Service Center, turned out to be a repository of materials currently under review by the Office of Information and Regulatory Affairs (OIRA) within the Office of Management and Budget (OMB).  In length and format, the W1 Core Items Booklet was very similar to the 2004 questionnaires that I had downloaded earlier (above).  Unfortunately, it was dated August 22, 2007, which meant that it might not have presented the final set of questions that were actually posed to the 2008 Panel.  I searched for "W1 Core Items Booklet" and found another entry at with what appeared to be the same PDF document.  On a webpage at, which appeared to be a website set up by three people who wanted to make the Federal Register more searchable, I found an indication that the Census Bureau was requesting OMB review of the Wave 6 topical modules for the 2008 Panel, with this statement:  "The core SIPP and reinterview instruments were cleared under Authorization No. 0607-0944."  A search for that authorization led to a different page, bearing the appealing certification date of January 28, 2010.  This webpage indicated that the relevant Information Collection Review (ICR) pertained to something known as the SIPP 2008 Panel Survey Instruments; and when I clicked on that link, I found myself back at the original webpage.  It seemed, in short, that the W1 Core Items Booklet dated August 22, 2007 seemed to be the final 2008 Panel Core Questionnaire.

I searched that 2008 Panel Core Questionnaire for references to "disability" and its cognates.  I found a number of such references.  I found no references to "impair" or its cognates in this Core Questionnaire, however, and the references to disability tended to be using accepted terminology rather than defining it -- referring, for instance, to "disability compensation," "disability insurance," and "disability benefits."  Because the SIPP is oriented toward income and benefits that people receive, it appears that it may be possible at least to use the data from its Core Questionnaire to make estimates about the portion of its target population for which disability affects the ability to work.  Whether that would prove necessary seemed to depend on what I could learn from SIPP's disability-related topical questionnaires.