In 2015, the U.S. Census Bureau conducted the 2015 National Content Test. This test was conducted to study the effect of different ways of asking demographic questions in preparation for the 2020 Census. Sample households could report online, by paper, or call a toll free number and report their data over the telephone with a Census Bureau interviewer. Interviewers used an online instrument to administer the questions and record the answers respondents gave. This online instrument was very similar to the one available to respondents who wanted to report online without any interviewer assistance.

This report documents the findings from interviewer debriefings held after the call-in operation was completed. The discussion during the debriefings focused on the online instrument used during the call-in operation. Suggestions were made to create a more concise series of questions to collect the names of the people living at the household, to use one question to collect race and Hispanic origin instead of separate questions to collect that information, and to provide information about re-entering the survey only if the respondent wants to end the survey prematurely. Other suggestions to improve the interview for a telephone mode were also made.