Study Search Results Your query returned 2 results. Series results are grouped under the most relevant study. You can ungroup series results. Use the search box below to revise your search, or start a new search. Results per page: 25 50 100 Sort by: Title A-Z Released/Updated Time Period Most Cited in ICPSR Bib. Most Downloaded (?) Study Title/Investigator 1. Aging in the Eighties: America in Transition, 1981 (ICPSR 8691) National Council on the Aging 2. American Perceptions of Aging in the 21st Century [APA21], 2000 (ICPSR 3326) Cutler, Neal E.; Whitelaw, Nancy A.