Identify Specific Selection Criteria

Focus on and pull out those characteristics that are unique to your product and not just general categories of the population. For example, experience using a cell phone and a camera may qualify as a requirement for a product that combines the two. But, because the product will be used by all age groups, you need not screen for a particular age group to include in your test sample.
Later, as you are acquiring participants, you can simply make sure that you get a mix of different ages.
To follow the example for the hotel reservations web site, your objective is to learn what differences there are in how different types of travelers make hotel reservations. The team decides it wants to see whether there are differences between rewards members and travelers who are not members of the rewards
program. To select participants, then, some criteria are:
■ Are they members of our hotel rewards program? We want some of each, split into equal sized groups, if possible.
■ Are they members of nny rewards program? For participants who are not members of our program, do they ever belong to rewards programs? For this test, we want one group of people who do not join rewards
programs.
Can you see where you might end up with questions to ask potential participants from this?

For the banking example, let's focus on just the back office folks for now. The objective of the test is to learn whether users who are new to the back office can use the new system as efficiently and effectively as those who have extensive knowledge of the particular operations of this back office. Is it possible that the new system could cut down on training time? To select participants to help you find this out, you will need workers who have been in their jobs for a long time (whatever you and your team determine is an appropriate amount of time), but also some who have been through little or no training. So, some selection criteria might be: