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Lowering response rates may be a slippery slope

I have read a couple of recent studies that compared early to late responders and concluded that late responders did not add anything to estimates.

I have a couple of concerns. The first concern is with this approach. A simulation of this sort may not lead to the same results if you actually implement the truncated design. If interviewers know they are aiming for a lower response rate, then they may recruit differently. So, at a lower response rate, you may end up with a different set of respondents than this type of simulation would indicate.

My second concern is that it is always easy to conclude that a lower response rate yields the same result. But you could imagine a long series of these steps edging up to lower and lower response rates. None of the steps changes estimates, but cumulatively they might.

I have this feeling that we might need to look at studies like this in a new way. Not as an indication that it is OK to lower response rates, but as a challenge to redesign what we are doing to test that hypothesis. For instance, you might subsample cases to receive the "unproductive" effort rather than completely truncate it. More than that, you might use this as evidence that "phase capacity" has been reached and try something else.

This all comes down to, when have we done due diligence to address the nonresponse challenge?


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