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“The question protocol”, as suggested by Richard Rutter, is a handy heuristic to evaluate the data fields of a form:
When designing a form, you can ensure you are gathering only pertinent information by always invoking the question protocol. The question protocol forces you – and your organization – to ask yourselves why you are requesting a piece of information from a customer. Getting to the bottom of why you’re asking a question means determining precisely how you will be using the answer, if at all.
Considering that every data point collected is a burden for the user who has to provide it, as well as a burden for the recipient who has to deal with it responsibly and in compliance with privacy laws, it is crucial to always cross-check the necessity for each and every one of them – the suggested 10-step questionnaire lists a convenient set of questions for reflection.
Or, condensed into one tweet:
This “minimum viable data” concept brings to mind the “minimum actionable dataset” (MAD) approach suggested by Chris Stacey in 2014: