The purpose of the 2010 Census Deadline Messaging and Compressed Mailing Schedule Experiment was to determine if an increase in census mail response and speed of response could be realized (without decreasing data quality) by including a due date or deadline message on various mailing pieces and/or by sending the census mailing pieces closer to Census Day.

Self-Response Options Research Question H.1: Can we improve mail response with the use of deadline messaging and/or a compressed mailing schedule?

One component of the 2003 National Census Test tested the inclusion of a due date on the envelope of the initial questionnaire package. While the inclusion of a due date on the outgoing envelope of the initial questionnaire mailing package did not affect the overall cooperation rates, it did increase the speed of the mail response (Bouffard, Brady, & Stapleton, 2004). Deadline messaging was tested again as part of a small multi-purpose test in the 2006 Decennial Short Form Experiment. The results showed that the combined effect of a compressed mailing schedule with deadline messaging yielded higher response rates without negatively impacting data quality (Martin, 2009). Further, there was also evidence that the treatment contributed to a within-household coverage improvement. However, the 2006 Decennial Short Form Experiment was not able to differentiate the effects of the deadline messages from the compressed schedule and was not able to analyze the effects of deadline messaging on the speed of mail returns. The 2010 Census Deadline Messaging and Compressed Mailing Schedule Experiment was designed to analyze these main effects in isolation, as well as in combination.