Dumas & Redish lay-out the steps and tactics for recruiting participants; those include: Finding Appropriate Participants, Reaching and Screening Potential Participants, Deciding Who Should Recruit Participants, Knowing What to Say When You are Recruiting, Arranging for Payment or Other Incentives, and Having a Back-up — But Not Double Booking
While testing non-representative participants may reveal some high-level problem, they will inevitably result in invalid and misleading feedback. The authors present 2 major problems: user-tolerance and user-understanding of language used throughout an interface may vary greatly from expert to novice user.
It may be that you will find the appropriate participant by browsing through your competitor’s customer-list or your own list where customers have purchased an older version of your product for instance. Those lists can be difficult to access, but those participants are more likely to be your target-audience and will be willing to show-up and try it out as it is relevant to their job or specific goals.
Using company employees can lead to inappropriate results as they may be familiar with the language used and may have been in contact with some parts of the development process of the product. As a resource, the authors suggest working with temporary agencies, advertising, networking, and working with professional associations.
Reaching and Screening Potential Participants concerns selecting participants according to a set of criteria that define your different end-users in terms of their job description, expertise, and so forth. Creating subgroups of participants as you recruit helps you determine whether you would want them to join your test or to attend a later test. Those typically take the form of phone-interview or physical questionnaire to be filled out. Depending on the subgroups you have defined, your questions will have to be specific and short. Additional information about participants may eventually force you to create a new set of subgroups.
Reaching participants is probably the most important part of the process. How do you get people interested and excited about a product? An introductory letter involves introducing the type of product as it relates to the participant’s goals or practice for instance, preparing them for the environment where they will be tested and the protocol employed (i.e. you will have to use a product while verbalizing your thoughts, etc.), indicating the length of the test, and mentioning the type of compensation for participating (money, product samples, etc.)
Who Should Recruit Participants?Clearly, if you are not a good people’s person then by all means get someone else to do the recruiting for you. Having an excited voice at the other end of the phone is what tells you this person is interested and will try his/her best to show up.
How Many Calls It Will Take? According to Dumas & Redish, it may take from 4 up to 15 phone calls to find one participant who is interested in the product and who corresponds to one of your set subgroups. In their experience:
The more specialized skills and experience you need, the more calls you should expect to make.” (p.145)
Depending on how specialized you seek your participants to be, you will want to allow yourself enough time for finding them prior to your ideal testing date. This means starting your search a month in advance. Some participants will be able to attend a test with a one or two days notice. One solution to participants forgetting the show-up or not being able to due to personal or unavoidable reasons would be, as the writers suggest, to prepare a one week or two days reminder before the scheduled date.
Another practical tactic would be to send a confirmation email or message that they can go back and refer to when the test approaches. This letter would include pretty much the content of the introduction letter, the date, time and place, as well as a contact they can use in case they get lost on the way or need to reschedule. This also means that you need to be ready to test on other days in case of no-shows.