Researchers put a lot of effort into developing survey questionnaires designed to measure key outcomes of interest for their impact evaluations. But every now and then, despite efforts piloting and fine-tuning surveys, some of the questions end up “not working”. The result is data that are so noisy and/or missing for so many observations that you may not want to use them in the final analysis. Just as pre-analysis plans have a role in specifying in advance what variables you will use to test which hypotheses, perhaps we also want to specify some rules in advance for when we won’t use the data we’ve collected. This post is a first attempt at doing so.