The community coinvestigators and AAP members were instrumental in creating promotional materials that would resonate with caregivers while seeking to use understandable and respectful language. We shared a brief description of the LEP that could be copied and pasted into an email to make it easier for others to promote the opportunity. Our team also developed a printable flyer to advertise the opportunity to join the LEP (Multimedia Appendix 1). The flyer was developed in English and Spanish to account for the large population of Spanish-speaking caregivers; it included photos of caregivers of different genders and racial and ethnic identities, specified that all responsibilities were virtual, and indicated that the opportunity was paid, though the amount of compensation was not included [26]. We omitted compensation details to minimize interest from individuals who were primarily financially motivated, including individuals pretending to be caregivers.

Our team developed an interest survey to act as an initial screening tool for those wanting to join the LEP (Multimedia Appendix 2). In creating the survey, we sought to balance the competing priorities of gathering information relevant to the caregiver context without creating an undue workload. The first step in creating the interest survey was to identify the primary and secondary variables across which representation was important. These variables were selected through a review of the caregiving literature and full team consensus-building discussions, and included dimensions of sociodemographics, caregiving experience, and prior research engagement experience [26-30]. In addition to these variables, we inquired about applicants’ reasons for their interest in joining the LEP, whether they had engaged in research before, and how the caregiver learned about this opportunity. The full interest survey can be found in Multimedia Appendix 2 and was also available in Spanish.

All team members, including principal investigators, the AAP, and community coinvestigators, were actively engaged in distributing promotional materials. Community organizations and research networks or registries also shared the opportunity. All were asked not to share the survey on social media to prevent fraudulent responses [31]. After the survey had been live for 2 weeks, we reviewed the maximum variance sampling matrix (see “Step 5: Selecting Interviewees Using Maximum Variance Sampling” section) to understand who had expressed interest and identified key gaps in representation. We used this information to determine which additional partners to engage.

Our objective was to create an LEP with a broad range of identities and experiences relevant to caregiving for adults with chronic health conditions, positioning the LEP to reflect key dimensions of variability found among US caregivers. To this end, we used a maximum variance sampling approach to identify which applicants to interview [32]. To do this, a matrix was created listing each interested individual by the maximum variance sampling criteria. In this matrix, each column represents an eligible applicant, and each row represents a sampling criterion (eg, relationship to care recipient, US region, and gender). Table 2 provides an example of a maximum variance sampling matrix.

We prioritized variability in characteristics that are demonstrated to shape the caregiving experience, while acknowledging that we could not capture every relevant factor [27]. In terms of demographics, we sought variability across race or ethnicity, gender, and geographic location. In terms of caregiver experience, we prioritized variability across caregiver relationships, cohabitation status, and chronic conditions. In terms of research engagement experience, we sought a mix of caregivers with and without research engagement experience. For those with experience, we sought variability in the type and duration of engagement. To the extent possible, we also attended to additional factors in constructing our maximum variance sample, including identities associated with health disparities and other caregiver and engagement experiences.

Because the LEP size was intentionally small, it was not possible to represent every combination of identities and experiences. Rather, applicants with multiple characteristics of interest were prioritized. For example, a research team might identify a potential interviewee who is a female caregiver of a parent living in the Northeast. The team would then look for a caregiver who differed in terms of their gender, relationship to the care recipient, and/or geographic location. This was the process used by 1 principal investigator to review the matrix and make interviewee recommendations based on prioritized criteria to the rest of the team. Team members then reviewed the matrix to suggest additional interview candidates.

Each potential LEP member was invited to participate in a 30-minute interview with the dual principal investigators and the project manager. A coinvestigator fluent in Spanish attended the interviews to provide interpretation. Interviewers began by providing background information on the goal of the broader research project and the required and optional responsibilities of the LEP. Interviewees were informed that they might be asked to assist with study activities such as the creation of promotional materials, the development of an interview guide, the analysis of interview data, survey development, and the dissemination of findings. An example question asked of interviewees was as follows: “Can you start out by telling us why you are interested in joining the lived experience panel?” Interviewees were invited to ask any questions or express any concerns. The full interview guide can be found in Multimedia Appendix 3.

Following each interview, 3 interviewers discussed the applicants’ responses and reviewed their sociodemographic variability as described in the maximum variance sampling matrix. After 8 interviews were completed, the interview team met to discuss an initial set of invitations to join the LEP. Five applicants were selected and emailed invitations to join. The interview team then conducted 3 additional interviews with the goal of inviting 2 additional applicants.

Email invitations indicated our desire for the LEP member to join and included a statement that we would follow up with study onboarding activities, such as setting up payment processes, should they choose to accept our invitation. We also noted that the first LEP meeting would occur approximately 2 weeks from the date of the invitation, so that the LEP could advise on recruitment for the research study, and we noted that future meetings would be scheduled well in advance with consideration of their availability. Prior to the first meeting, LEP members were asked if they would like a Spanish translator present, and all members declined.

We assessed (1) the time spent forming the LEP, from developing promotional materials to the final formation of the LEP; (2) the success (in terms of the number of applications) of each channel used to reach potential LEP members; and (3) the sociodemographic and caregiving characteristics of those who applied, were interviewed, and were invited to join the LEP.

We obtained LEP members’ feedback on the LEP formation process through an open-ended question: “From your perspective as a potential LEP member, what felt easy or challenging about recruitment?” Responses were collected from LEP members via email and through discussions at an LEP meeting. We summarize the responses of LEP members to these questions.

The entire promotional process, from drafting and finalizing materials to closing the interest survey, spanned from May 2025 to June 2025. The interest survey was published and distributed beginning on June 3, 2025, and remained open for 4 weeks, during which time we received a total of 44 applications to join the LEP. Most applicants who received an interview invitation (10/11) responded on the same day it was sent. All invitees scheduled their interviews for within 8 days of receiving the invitation. All but 1 invited LEP member accepted the invitation to join on the day it was sent. Figure 1 provides a detailed LEP creation timeline.

The LEP opportunity was distributed directly via 12 distinct community coinvestigators, academic advisors, and community partners. Of the 44 applicants, 14 (31.8%) heard about the opportunity through a promotional channel other than our direct partners, signaling that the opportunity was further disseminated through word-of-mouth. Table 3 provides the number of applicants gained through each promotional strategy.

We conducted 11 interviews and extended 7 invitations to join the LEP. All participants who were invited to join accepted the invitation. Table 4 provides the demographic and clinical characteristics of those who applied, were interviewed, and were invited to join. It took a median of 23.01 (IQR 37.05) minutes to complete the interest survey.

Five LEP members provided feedback by email, and 2 of them expanded on their comments during a subsequent live LEP discussion.

In this study, we describe a process for intentionally and respectfully forming an LEP and evaluate its feasibility. We worked with a broad range of partners to form an LEP of 7 caregivers, previously unknown to the principal investigators. Moreover, the resulting LEP included caregivers with a broad range of characteristics aligned with the diverse lived experiences of the US caregiver population [26]. Feedback from LEP members indicated that while some experienced the process of joining as relatively smooth, others identified areas for improvement. LEP members’ decisions to join were shaped by their experiences at each step, from hearing about the opportunity to completing the interest survey to engaging in the interview. With refinements to better support applicants, the process for forming an LEP described here can be adopted to facilitate research engagement across multiple patient and caregiver populations.

We identified 2 key takeaways from our process of forming an LEP. First, we found success in promoting the LEP opportunity through our trusted community partners. Relationships with these partners allowed us to quickly form an LEP that is diverse in the characteristics that shape the caregiving experience. We recommend that research teams focused on building variable LEPs prioritize first building relationships with community members. As a second takeaway, we were rewarded for our strategy of intentionally selecting questions for the LEP interest survey in ways we did not predict. Not only did the selected questions allow us to rapidly narrow a pool from 44 applicants to 11 interviewees to 7 invitations to join, but the questions served a second purpose of building trust with applicants, with 1 LEP member describing the survey questions as well-justified and meaningful. We recommend that research teams invest time and thought into crafting an interest survey that provides actionable information for researchers and communicates respect to applicants.

In addition to our key takeaways, we learned 3 lessons that will shape how our team forms LEPs going forward. First, with input from our LEP members, we learned that our interview process could have more clearly conveyed the expectations and responsibilities of LEP membership. LEP members’ desire for specificity raises an important question for future work: how to offer concrete information about engagement responsibilities while allowing LEP members to shape the nature of their involvement. One approach is to introduce an LEP charter during the interviews—a document describing the scope and commitment of LEP engagement. During interviews, we would describe a formal process for revising the charter so that it is continuously responsive to LEP members’ needs and goals. For example, a group charter could address attendance expectations, alternatives to attendance if meeting as a group is not possible or preferred, processes for member withdrawal, and approaches to facilitating balanced participation between LEP members. The introduction of a charter and its collaborative codevelopment could serve the equally important purpose of building trust with potential LEP members.

Second, the maximum variance sampling approach introduces a central tension: decisions made to maximize variability may inadvertently imply to nonselected applicants that the researchers are not interested in their experiences. This tension felt especially acute when variability was the key reason for not inviting an interviewed applicant, as we felt connected to the interviewees and knew more about the depth and nuance of their experiences. In future applications of the maximum variance sampling approach, we will emphasize throughout the interest survey and interview process that all caregiving experiences are meaningful, even though the limited size of LEPs means not all caregivers can be invited to join. We will explicitly state that our selection decisions prioritize variability, not because it is the only relevant guiding principle, but because diverse LEPs strengthen the relevance and impact of the research they inform [33,34]. As another attempt to respect applicants’ time and contributions, in future iterations of LEP formation, we will interview and accept applicants sequentially rather than in batches so that we do not interview many more people than we can invite to join.

Finally, although we were successful in disseminating the LEP opportunity to a diverse community of caregivers, certain gaps in our applicant pool persisted. For example, we heard from few caregivers who identified as Latino, who had less than a high school education, who identified as LGBTQIA+ (lesbian, gay, bisexual, transgender/transsexual, queer, and other minority sexual orientations and gender identities), or who lived in the southwestern region of the United States. These gaps highlight the need for our team to leverage different promotional strategies (eg, posting flyers in-person rather than relying on digital dissemination) and to further expand and diversify our community partnerships.

The findings of this paper bring to light a second, central tension: engaging patients and caregivers requires a significant, and not directly compensated, investment of time and resources. Our formation of an LEP hinged on existing relationships with community partners, in which trust was sufficient for them to agree to be coinvestigators or assist with the dissemination of LEP promotional materials. To those intimidated by this proposed groundwork, we offer 3 forms of encouragement. First, researchers new to patient and caregiver engagement can reach out to colleagues and mentors with long-standing relationships in communities of interest to help accelerate the building of trust. Second, investments in community relationships do not signify a net loss of time. Instead, these investments are reallocations of time toward earlier phases of the work, increasing our productivity downstream in meeting LEP formation milestones and the successful dissemination of materials. Finally, there are undoubtedly additional, innovative strategies for reaching diverse and previously unknown patients and caregivers, and teams that blend research and community perspectives are more likely to uncover them. These maximally variable LEPs, comprising people embedded in patient and caregiver communities, can substantially enhance the relevance and impact of any research they support.