How We Recruit Experts for a Delphi Study: Our Six-Step Email Playbook

by Manuela Verde and Jeffrey Franc

In the vast landscape of survey methodologies, Delphi studies hold a unique position due to their iterative nature and reliance on expert consensus. Recruiting participants for these surveys, however, is no small feat. The challenge lies in identifying and engaging individuals with the precise expertise needed to generate meaningful insights. Furthermore, as Delphi studies are iterative and time consuming, keeping the experts engaged throughout the process requires special attention.

As professionals who have orchestrated numerous Delphi studies, we have navigated these complexities firsthand, having recruited hundreds of experts. Despite our experience, we still find the process challenging, which is why we've refined a unique method over time.

Interestingly, we have also been on the other side, experiencing the selection process as experts ourselves. This dual perspective has not only deepened our appreciation for the intricacies involved but has also fueled our commitment to refining the process.

Drawing from our experiences as both designers and participants, we have developed a streamlined six-step approach to expert recruitment. This methodology, grounded in six distinct principles, has consistently delivered excellent results.

Step 1: Personalized Recruitment Email

The cornerstone of effective recruitment is a personalized email from someone who has a direct relationship with the expert. Academics receive countless anonymous survey invitations, making it easy for them to overlook generic requests. A personalized message cuts through the noise.

This approach ensures the recipient feels valued and is more likely to engage.

In cases where we do not have direct access to the experts, we often enlist the help of local champions to serve as liaisons. For instance, for our recent international Delphi study, we recruited one co-author for each world region. Co-authors served as a vital local link for the international recruitment process. Experts received the initial recruitment email from a local champion who was known to them rather than an anonymous “Dear researcher” email, which is frequently ignored.

For example:

We recommend that these emails are sent from the personal email account, not from an automated email service. Furthermore, we consider the personalized recruitment email as another example of “clarity beats cleverness.” The email articulates clearly the responsibilities (approximately 120 minutes of their time) and the limitations of the benefits (experts are acknowledged but are not co-authors).

If experts respond affirmatively to the email, the original sender will usually reply with something simple like:

The email is sent in .cc to the study coordinator, who can send the next email at step 2.

Step 2: Enrollment Email

Once the expert has expressed interest, the next step is the enrollment email. This email is usually sent by the study coordinator or primary investigator. It provides comprehensive information about the study. It should include formal consent documents from the relevant ethical body and invite the expert to ask any questions. It should also mention that they will soon receive an email from the automated survey platform, such as Stat59, with further instructions on how to proceed.

Experts are also invited to seek additional clarification about the study by replying to the email.

Generally, we have had very good luck with ethics boards of most universities not requiring a signed consent document. Most will consider registering for the study online as implied consent. If your ethics granting body requires a signed consent, it should be indicated in this email, and signed consents collected by the study coordinator or primary investigator.

Step 3: Study Registration Email

The next email, typically from the automated platform like Stat59, will guide the experts on how to register for the first survey round. This email includes step-by-step instructions for creating a username and account, ensuring a seamless entry into the study. It's crucial that experts are anticipating this email, as automated messages often get overlooked by busy professionals. Setting this expectation in prior communications helps ensure they follow through.

For example, automated study registration emails from STAT59 look like this:

Following the personalized link in the email leads the expert directly to the first survey round. With STAT59 experts are invited to create their own unique username and password. In addition, they are given information about the privacy and security policies of STAT59. At the discretion of the primary investigator, the initial survey can also include consent to acknowledge the expert in the final paper or on social media.

Importantly, we do not send this automated email until the first survey round is ready for experts to complete. Experts may find it frustrating to go to the site, sign on, and find that the survey is not ready for them to complete.

Step 4: Next Round Reminder

Following the completion of each round of the Delphi study, experts receive a repeat invitation from the same platform, inviting them to participate in the next round. This ensures a smooth, continuous flow throughout the study. This email should contain explicit instruction on how to access the next round.

For instance, automated emails from STAT59 give the link to follow and instructions to use the previously created username and password.

A similar automated email is sent each time a new survey round opens.

Step 5: Reminder Emails

Busy experts often get sidetracked by their other commitments, leading to delays in survey completion. When this happens, we like to send a personalized reminder email from the same contact who initiated the recruitment in Step 1. This message includes personal anecdotes and highlights the critical importance of their input, gently urging them to complete the survey as soon as possible. This approach helps re-engage experts while respecting their busy schedules.

For example:

Step 6: Thank You

Experts who have completed all rounds of the Delphi study will have devoted considerable time and effort and deserve meaningful acknowledgment. While Delphi experts may not qualify for authorship on academic papers, we make a point to acknowledge them if they agree, either in the paper or on social media. For those who prefer to remain anonymous, a heartfelt thank you email expressing sincere gratitude for their contributions is highly appreciated.

For example:

Wrapping It Up: The Six-Step Expert Recruitment Playbook

In this blog post, Manuela Verde shares our proven six-step email strategy for successfully recruiting and retaining experts in a Delphi study. The process begins with a personalized recruitment email from a known contact or local champion to establish trust and interest. Once experts agree to participate, they receive an enrollment email from the study coordinator or principal investigator, providing detailed study information and consent documents. Next, a study registration email from an automated platform like Stat59 guides them through account setup. As the Delphi study progresses, experts receive next round reminder emails from the platform to ensure continued engagement. When participation lags, personalized reminder emails from the original recruiter help re-engage busy professionals. Finally, the process concludes with a sincere thank you email, offering either private or public acknowledgment for their valuable contributions.