Educational Testing Services, the US-based NGO that delivers the GRE and TOEFL, has produced a publication on “Connecting Graduate Admissions Practices with Goals”. This publication yields basically a set of questions, developed with practitioners, to be used by Master’s programmes to examine and critically reflect on their current admission process, its quality and effectiveness.
It hands discussion-starter questions both for the planning and the monitoring & evaluation of the admission process and in between looks critically at a) the information you need, b) the way you examine that information, and c) the way you arrive at a decision to accept or reject and applicant.
The guide falls short of making make an explicit distinction between a) the things students have to be good and how good they have to be at it (what you are looking for) and b) the things you use in the process like grades, tests and interviews (the things you are looking at). But implicitly, it asks the questions that help to make this distinction.