Participant recruitment for research involves a number of activities including sourcing eligible candidates, screening them, explaining the study, and keeping them motivated & incentivized throughout the study.
It’s typical for recruitment to take longer than anticipated, project costs to balloon due to recruitment challenges, and researchers to overestimate the number of participants available. Even in studies that succeed in recruiting large numbers of patients, participation rates are low; only 3-20% of the eligible participant pool chooses to participate.
Despite the fact that recruitment is a challenge, details about recruitment efforts and outcomes are rarely published, resulting in limited knowledge about why recruitment rates vary between studies and what the most successful approaches are for recruiting study participants.
In this guide we offer some tips to make your participant recruitment easier.
When recruiting for small sample studies, behavior and attitudes are more important than demographics. For example, when conducting research for a furniture company’s online cart, it is better to find participants who are in the market for new furniture than it is to simply replicate the company’s current customer demographics.
In terms of raw numbers, usability tests can be run with a low number of participants—around 5 is adequate to surface key problems. When interviewing, aim to talk with roughly 10 people. Diary studies are typically conducted with 12 – 15 participants. These are all examples of ‘small sample’ studies. Surveys are on the other end of the spectrum, often requiring hundreds of responses to get meaningful, statistically significant results.
Before you start recruiting, here are some questions to ask yourself:
Representative, well-spoken, and thoughtful participants can provide invaluable insights, yet finding such ideal participants and getting them to commit is often the hard part. Here are a few ideas to start creating your ‘research recruitment funnel.’
If you’re conducting research for your own product or service, reach out to people from your own customer database. However, watch for bias — they might be ‘fanboys’ and love your product, or they may loathe it. Obviously, recruiting existing customers doesn’t work if you’re trying to figure out why people don’t use your product/service.
If you’re interested in people’s motiviations for trialling your product / service, or the problems they’re hoping to solve, recruiting them before they sign up could be beneficial. Use a tool like Ethn.io to show a form on your website that prompts visitors to sign up for research.
Create a Google Form and share the link on Twitter, LinkedIn, and Facebook. To increase your response rate, mention your incentive in the message, and how much effort someone needs to spend. For example, “Please help me learn about student life on campus! $100 for only 30 minutes of your time.” You’ll get a wide variety of people responding, so the emphasis will be on your screener (see below) to weed out unsuitable candidates.
Reach out to your friends or family, and ask your colleagues to do the same. Let them know your criteria, and optionally offer them a referral bonus if they find someone who ends up participating in your study.
There are plenty of recruitment agencies who have large pools of people available for research, although it doesn’t come cheap. In your screener you will need to pay special attention to elimate ‘professional research participants’ who know how to game the system to get the reward.
If you’re conducting a quick usability test, try a bit of guerrilla research — ask people in cafes to look at your prototype in exchange for a coffee or 🍰 cake!
Don’t waste time by making participants go through a lengthy screener before getting to the questions that eliminate most people. Ask those questions first, so only the most likely candidates must go through all of the questions.
Eliminate people who may have a conflict of interest or who have too much insider knowledge. For example, if you were conducting usability testing on an airline’s website with travelers, you should screen out people who work for that airline or a competitor.
Ensure that the participants’ experience with technology matches that of your user groups. You’ll often want to eliminate people with too little or too much technical knowledge, unless their level of experience is appropriate for your project. In a usability test, you don’t want participants to confuse user interface problems with the problems new computer users face in general. Similarly, you won’t usually want to test with participants who are developers or designers as they bring a level of expertise and a focus that is not representative of a typical user.
Qualitative research is all about making people talk (or write). There are few things worse than someone who gives only one-word answers, and it requires a lot of work to drag useful information out of such people. To determine how expressive people are, ask a few open-ended questions that relate to the topic of your study.
Make sure participants know what your expectations are for the study, and that they are available throughout the duration. If it’s only a 30 minute usability test, this shouldn’t be a problem, but if you are running a diary study over two weeks, make sure they know they need to stay committed throughout.
People who frequently supplement their income by participating in user research will say and do whatever it takes to get into a study. It’s often too easy for them to figure out the correct responses and avoid being eliminated. Ask open-ended questions about how often they participate in research, and include multiple elimination questions during the screener.
Getting the insights you need will take some involvement with participants throughout the study. Plan to check in with participants or use Dovetail to give periodic reminders as needed (each day or every few days). For participants that are engaged and creating appropriate snippets, recognize their efforts and ask them to keep up the good work. For participants that are less engaged, give encouragement or offer to answer any questions they may have to get them on track. Let participants know up front that you will be reaching out throughout the study and agree on a means of contacting them, so you can give encouragement or ask for clarification without being overly intrusive.
Diary studies require time and dedication from participants. To ensure you get the level of involvement you need from participants, provide an incentive that will keep them engaged. This compensation is typically much more than what you would offer for a 60-minute usability test. Align the incentive with the amount of work required over the period of the study. Consider breaking apart the total incentive and offering smaller installments as participants reach specific milestones (e.g., 3 days of logging), to keep them motivated throughout the duration of the study.
Once you’ve recruited participants, try Dovetail to run your study. Dovetail helps you design your study, collect data, analyze results, and share what you’ve learned. It’s completely free to get started.