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Undercoverage issues

I recently read an article by Tourangeau, Kreuter, and Eckman on undercoverage in screening surveys. One of several experiments on which they report explores how the form of the screening questions can impact eligibility rates. They compare taking a full household roster to asking if there is anyone within the eligible age range. The latter produces lower eligibility rates.

There was a panel at JSM years ago that discussed this issue. Several major screening surveys reported similar undercoverage issues.

Certainly the form of the question makes a difference. But even on screening surveys that use full household rostering, there can be undercoverage. I'm wondering what the mechanism is. If the survey doesn't advertise the eligibility criteria, how is that some sampled units avoid being identified as eligible? This might be a relatively small source of error in the survey, but it is an interesting puzzle.




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