The Survey of Income and Program Participation (SIPP) is a nationally representative sample to estimate the sources and amounts of income, labor force information, program participation and eligibility data, and general demographic characteristics.  The SIPP survey is a longitudinal survey which interviews the sampled respondents every 4 months, called a  wave.   The  survey  contains  a  set  of  core  questions  (asked  at  every  wave)  and  sets  of topical modules which are only asked during specific waves, e.g.  one the topics of child care, wealth, disability, and school enrollment.  The disability module has detailed ques- tions (the same questions as in the standard Activities of Daily Living and Instrumented Activities of Daily Living Battery) about many different aspects of disability.  Questions address physical and mental conditions affecting the persons in the household, including the use of mobility aids, vision and hearing impairments, speech difficulties, lifting and aer- obic difficulties, and the ability to function independently within the home (Brault 2012). The disability estimates from the SIPP have been referenced in the findings clause of the Americans with Disability Act.