In total, we purchased 5 ads in English, simplified Chinese, traditional Chinese, Korean, and Spanish and showed them on Facebook from June 16 to August 3, 2017. The California State University San Marcos Institutional Review Board approved the ads shown on Facebook. Following the recommendations by Thornton et al [11], the ads were concise, showed the affiliation of the research study with a university, and offered incentives for participation (Figure 1). The link in each Facebook ad connected to the study website, which stated the eligibility criteria for participating in the 30-minute Web-based survey in the respective language of the clicked ads (eg, clicking the Korean ad would lead to the study information presented in Korean).

When participants clicked on the Facebook ad, they were directed to the study website that provided a general description of the study and the inclusion criteria. On this website, participants interested in the study submitted their email address by entering it into the “email” submission box. Then, participants received a more detailed description of the study as well as a link to the Web-based survey via email. We directed participants who accessed the survey link from their email inbox to the Web-based survey cover page that described the study, which explained the inclusion criteria, study procedure, and data confidentiality and stated that their consent was given by continuing with the survey. The first 5 questions screened potential participants for eligibility by asking whether they were Asian or Latinx, lived in the United States, aged ≥18 years, diagnosed with cancer, and within 5 years of their cancer treatment. Participants who answered “yes” to each of the 5 questions were directed to complete the survey, which assessed their demographic and cancer diagnosis information, well-being, experience with the study, and interest in participating in future research studies. We did not report the data on well-being in this study. Participants who completed the survey were sent a US $10 Walmart eGiftcard.

The ad campaign was set up with a maximum daily budget of US $25 and ran for 48 consecutive days for a total spending of US $1,200.46 (June 16 to August 3, 2017). In total, the English, Spanish, Korean, and traditional and simplified Chinese ads generated 45,768, 34,261, 30,335, 21,230, and 13,041 impressions (ie, total number of times the ads were shown to Facebook users) and reached 31,299, 25,217, 8187, 7183, and 4915 people (ie, number of unique Facebook users who saw the ads), respectively. These impressions generated 420, 984, 307, 291, and 127 link clicks for the English, Spanish, Korean, and traditional and simplified Chinese ads, respectively. The average cost per click across the 5 ads was US $0.56 (see Table 1). Of the 2129 total link clicks that directed the potential participant to the study website, 115 people entered their emails after reading the study information and eligibility criteria (Figure 2). Due to 10 incorrectly submitted emails, 10 survey links were not delivered. Of the105 people who were sent the Web-based survey link, 36 (34.3%) clicked on the survey link and completed the initial screening questions. Of these 36 people who begun the survey, 29 (81%) were eligible and completed the Web-based survey (10 Chinese, 4 Korean, and 15 Latinx cancer survivors); however, 3 (10%) surveys were completed by a Chinese participant with the same internet protocol address and, thus, were excluded from subsequent analyses. In total, data from 4 surveys in English (3 by Latinx and 1 by Chinese participants), 4 surveys in Korean, 5 surveys in traditional Chinese, 1 survey in simplified Chinese, and 12 surveys in Spanish were analyzed. The cost per participant was US $46.17 (ie, total spending per number of completed Web-based surveys).

We combined the Chinese and Korean participants into 1 East Asian participant group. Of the 11 East Asian cancer survivors (mean age 55.91 [SD 10.03] years; 8/11, 73%, females), 91% (10/11) were first-generation immigrants (ie, foreign-born), 55% (6/11) obtained a college degree, and 9% (1/11) reported an annual family income <US $13,000. The majority (9/11, 82%) spoke Chinese or Korean but 64% (7/11) also reported the ability to speak English. Most of the East Asian cancer survivors had diagnoses of breast cancer (5/11, 46%) or lymphoma (3/11, 27%), and 55% (6/11) were in remission. Of the 15 Latinx cancer survivors (mean age 49.73 [SD 9.71] years; 13/15, 87%, females), 80% (12/15) were first-generation immigrants, 53% (8/15) obtained a college degree, and 47% (7/15) reported an annual family income <US $13,000. The majority (13/15, 87%) spoke Spanish, but only 20% (3/15) also reported the ability to speak English. Most of the Latinx cancer survivors had diagnoses of breast cancer (7/15, 47%) or colorectal cancer (3/15, 20%). See Table 2 for complete demographic and cancer diagnosis information.

We examined demographic differences between East Asian and Latinx cancer survivors. They did not significantly differ regarding age (P=.13), years lived in the United States (P=.10), education level (P=.92), generation status (P>.99), stage of cancer diagnosis (P=.35), time since diagnosis (P=.85), and treatment status (P=.82). However, Latinx cancer survivors were marginally more likely to only speak their heritage language (ie, limited English proficiency; P=.06) and marginally more likely to endorse an annual family income <US $13,000 compared with the East Asian cancer survivors (P=.09).

We examined participants’ experience with this study and their interest in participating in future research (Table 3). East Asian cancer survivors reported a lower ease of participation (eg, having technical difficulties accessing the survey) in this study than Latinx cancer survivors (mean 2.91 [SD 0.66] vs mean 3.47 [SD 0.52]; two-tailed t₂₄=2.41; P=.02). Both Latinx and East Asian cancer survivors reported that they enjoyed the opportunity to share their cancer-related experiences in this Web-based survey (mean 3.40 [SD 0.63] and mean 3.27 [SD 0.47], respectively; two-tailed t₂₄=0.37; P=.56). Both Latinx and East Asian cancer survivors indicated a willingness to participate in future cancer research studies through video or phone interviews with study researchers or sharing their cancer experiences through writing or voice recording (mean 3.00 [SD 0.54] and mean 3.00 [SD 0.63], respectively; two-tailed t₂₄=0; P>.99). The majority of Latinx and East Asian cancer survivors indicated having access to a smartphone (13/15, 87%, and 10/11, 91%, respectively).

This study demonstrated the feasibility and effectiveness of recruiting Latinx and East Asian cancer survivors via targeted advertisements on Facebook. With a focus on identifying cancer survivors who may benefit from participating in psychosocial intervention research (ie, within 5 years of cancer diagnosis), we examined their experience with our Web-based survey and their interest in participating in future research.

We found that the Facebook campaign was successful in recruiting a sample of Latinx and East Asian cancer survivors with different cancer diagnoses from various geographic regions of the United States. Latinx and East Asian cancer survivors recruited from Facebook enjoyed sharing their cancer experiences and reported their interest in participating in future psychosocial intervention studies ranging from Web-based focus groups to private emotional disclosure through writing or voice recording (eg, expressive writing interventions [16]). Furthermore, we found that all but 3 (23/26, 88%) participants had access to smartphones and, thus, could participate in Web-based or mobile-based psychosocial interventions that have become increasingly popular in recent years [17].

Most of the Latinx and East Asian cancer survivors were immigrants, female, and had breast cancer diagnoses. However, Latinx cancer survivors were more likely to speak only their heritage language (eg, Spanish) and reported a lower annual household income than the East Asian cancer survivors. These findings suggest that Facebook may be an especially effective source of recruitment for immigrant Latinx cancer survivors who are from lower socioeconomic backgrounds. Because this population represents a significantly understudied and underserved population with significant cancer health disparities [5], our findings build upon a growing number of studies that have demonstrated the success of using Facebook to recruit harder-to-reach medical populations [18].

A significant portion of potential participants did not participate in the Web-based survey after receiving the survey link in their emails. Although speculative, these participants may have submitted their emails on the spur of the moment after clicking the Facebook advertisement without carefully reading the study description and inclusion criteria on the website, and only later learned from the received email that they were ineligible. Alternatively, it is also possible that they had difficulty trusting the researchers and the email they received [9]. Although we included the affiliated university logo where possible (eg, on the Facebook ad and study website), the research team’s email used to send the survey link was not from a university-affiliated email address. Perhaps using a university-affiliated email address would have increased the participants’ trust and willingness to complete the survey. Nonetheless, we successfully recruited 11 East Asian and 15 Latinx cancer survivors in 48 consecutive days of recruitment. Notably, we only recruited through the paid Facebook advertisement platform and did not utilize other opportunities that were freely available on Facebook. For example, we did not manually post our ads on cancer-related Facebook pages and groups [19]. Researchers considering Facebook to recruit ethnic minority cancer survivors can potentially maximize their success by utilizing both free and paid advertisement strategies.

While we found support for the feasibility and effectiveness of recruiting East Asian and Latinx cancer survivors from Facebook, our study has several limitations. First, we did not include a direct comparison with traditional methods of recruitment (eg, physician referrals or flyering), so we could not determine whether Facebook recruitment is a more efficient or cost-effective method than traditional methods. However, the costs of hiring research staff with language abilities to distribute flyers and screen potential participants are likely more expensive and time-intensive than the minimal time and personnel needed for recruitment through Facebook. Although we cannot speculate on the demographic similarities or differences between the East Asian and Latinx cancer survivors recruited through Facebook or in person, a growing number of studies have found minimal differences between Web-based and in-person recruitments [11]. However, the feasibility and effectiveness of recruiting through other social media platforms (eg, Craigslist) requires future testing. Moreover, given that the study was conducted through the Web, we could not verify the veracity of the information provided by the participants. It is also unclear whether participants who clicked on the ads and viewed the study page were eligible but not interested in participating or whether they were ineligible owing to having completed cancer treatment over 5 years ago. Lastly, given the focus on Chinese and Korean cancer survivors in this study, the generalizability of our findings to other Asian subgroups (eg, Filipino and Hmong) from Facebook remains to be tested.

The recruitment of ethnic minority cancer survivors into cancer research has been a longstanding issue. With the potential to address this problem, we found that Facebook was a feasible and effective platform for recruiting Latinx and East Asian cancer survivors who may be interested in future psychosocial intervention research. Facebook was successful in reaching participants with different cancer diagnoses who come from various geographic regions. Ethnic minority cancer survivors are regarded as a challenging population to recruit, partially owing to limited English proficiency and low socioeconomic status. The Latinx and East Asian cancer survivors who participated in this study reported favorable experiences with the Web-based survey and reported interest in participating in future research studies. Future research studies should compare demographic and psychosocial differences between participants recruited from traditional and Web-based sources.