Comparison of 4 recruiting strategies in a smoking cessation trial

Recruitment in Appalachian, Rural and Older Adult Populations in an Artificial Intelligence World: Study Using Human-Mediated Follow-Up

BACKGROUND

Participant recruitment in rural and hard-to-reach (HTR) populations can present unique challenges. These challenges are further exacerbated by the need for low-cost recruiting, which often leads to use of web-based recruitment methods (eg, email, social media). Despite these challenges, recruitment strategy statistics that support effective enrollment strategies for underserved and HTR populations are underreported. This study highlights how a recruitment strategy that uses email in combination with follow-up, mostly phone calls and email reminders, produced a higher-than-expected enrollment rate that includes a diversity of participants from rural, Appalachian populations in older age brackets and reports recruitment and demographic statistics within a subset of HTR populations.

OBJECTIVE

This study aims to provide evidence that a recruitment strategy that uses a combination of email, telephonic, and follow-up recruitment strategies increases recruitment rates in various HTR populations, specifically in rural, older, and Appalachian populations.

METHODS

We evaluated the overall enrollment rate of 1 recruitment arm of a larger study that aims to understand the relationship between genetics and substance use disorders. We evaluated the enrolled population's characteristics to determine recruitment success of a combined email and follow-up recruitment strategy, and the enrollment rate of HTR populations. These characteristics included (1) enrollment rate before versus after follow-up; (2) zip code and county of enrollee to determine rural or urban and Appalachian status; (3) age to verify recruitment in all eligible age brackets; and (4) sex distribution among age brackets and rural or urban status.

RESULTS

The email and follow-up arm of the study had a 17.4% enrollment rate. Of the enrolled participants, 76.3% (4602/6030) lived in rural counties and 23.7% (1428/6030) lived in urban counties in Pennsylvania. In addition, of patients enrolled, 98.7% (5956/6030) were from Appalachian counties and 1.3% (76/6030) were from non-Appalachian counties. Patients from rural Appalachia made up 76.2% (4603/6030) of the total rural population. Enrolled patients represented all eligible age brackets from ages 20 to 75 years, with the 60-70 years age bracket having the most enrollees. Females made up 72.5% (4371/6030) of the enrolled population and males made up 27.5% (1659/6030) of the population.

CONCLUSIONS

Results indicate that a web-based recruitment method with participant follow-up, such as a phone call and email follow-up, increases enrollment numbers more than web-based methods alone for rural, Appalachian, and older populations. Adding a humanizing component, such as a live person phone call, may be a key element needed to establish trust and encourage patients from underserved and rural areas to enroll in studies via web-based recruitment methods. Supporting statistics on this recruitment strategy should help researchers identify whether this strategy may be useful in future studies and HTR populations.

Combating Fraudulent Participation in Urban American Indian and Alaska Native Virtual Health Research: Protocol for Increasing Data Integrity in Online Research (PRIOR)

BACKGROUND

While the advantages of using the internet and social media for research recruitment are well documented, the evolving online environment also enhances motivations for misrepresentation to receive incentives or to "troll" research studies. Such fraudulent assaults can compromise data integrity, with substantial losses in project time; money; and especially for vulnerable populations, research trust. With the rapid advent of new technology and ever-evolving social media platforms, it has become easier for misrepresentation to occur within online data collection. This perpetuation can occur by bots or individuals with malintent, but careful planning can help aid in filtering out fraudulent data.

OBJECTIVE

Using an example with urban American Indian and Alaska Native young women, this paper aims to describe PRIOR (Protocol for Increasing Data Integrity in Online Research), which is a 2-step integration protocol for combating fraudulent participation in online survey research.

METHODS

From February 2019 to August 2020, we recruited participants for formative research preparatory to an online randomized control trial of a preconceptual health program. First, we described our initial protocol for preventing fraudulent participation, which proved to be unsuccessful. Then, we described modifications we made in May 2020 to improve the protocol performance and the creation of PRIOR. Changes included transferring data collection platforms, collecting embedded geospatial variables, enabling timing features within the screening survey, creating URL links for each method or platform of data collection, and manually confirming potentially eligible participants' identifying information.

RESULTS

Before the implementation of PRIOR, the project experienced substantial fraudulent attempts at study enrollment, with less than 1% (n=6) of 1300 screened participants being identified as truly eligible. With the modified protocol, of the 461 individuals who completed a screening survey, 381 did not meet the eligibility criteria assessed on the survey. Of the 80 that did, 25 (31%) were identified as ineligible via PRIOR. A total of 55 (69%) were identified as eligible and verified in the protocol and were enrolled in the formative study.

CONCLUSIONS

Fraudulent surveys compromise study integrity, validity of the data, and trust among participant populations. They also deplete scarce research resources including respondent compensation and personnel time. Our approach of PRIOR to prevent online misrepresentation in data was successful. This paper reviews key elements regarding fraudulent data participation in online research and demonstrates why enhanced protocols to prevent fraudulent data collection are crucial for building trust with vulnerable populations.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04376346; https://www.clinicaltrials.gov/study/NCT04376346.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/52281.

Designing Studies to Inform Tobacco Harm Reduction: Learnings From an Oral Nicotine Pouch Actual Use Pilot Study

Background

Introduction of new tobacco products in the United States, including those that may be lower on the risk continuum than traditional combustible cigarettes, requires premarket authorization by the US Food and Drug Administration and information on the potential impact of the products on consumer behaviors. Efficient recruitment and data capture processes are needed to collect relevant information in a near-to-real-world environment.

Objective

The aim of this pilot study was to develop and test a protocol for an actual use study of a new tobacco product. The product included in this study was a commercially available oral nicotine pouch. Through the process of study design and execution, learnings were garnered to inform the design, execution, analysis, and report writing of future full-scale actual use studies with tobacco products.

Methods

A small sample (n=100) of healthy adult daily smokers of 7 or more cigarettes per day were recruited to participate in an 8-week prospective observational study conducted at 4 geographically dispersed sites in the United States. A smartphone-based customized electronic diary (eDiary) was employed to capture daily tobacco product use, including 1 week of baseline smoking and 6 weeks during which participants were provided with oral nicotine pouches for use as desired.

Results

Online screening procedures with follow-up telephone interviews and on-site enrollment were successfully implemented. Of 100 participants, 97 completed the study, with more than half (59/99, 60%) identifying as dual- or poly-users of cigarettes and other types of tobacco products at baseline. There was more than 90% (91-93/99, 92%-94%) compliance with daily eDiary reporting, and the majority (92/99, 93%) of participants expressed satisfaction with the study processes. Product use data from the eDiary indicated that after an initial period of trial use, pouches per day increased among those continuing to use the products, while per day average cigarette consumption decreased for 82% (79/97) of all study participants. At the end of the week 6, 16% (15/97) of participants had reduced their cigarette consumption by more than half.

Conclusions

The design of this study, including recruiting, enrollment, eDiary use, and oversight, was successfully implemented through the application of a detailed protocol, a user-friendly eDiary, electronically administered questionnaires, and remote monitoring procedures. High-resolution information was obtained on prospective changes in tobacco product use patterns in the context of availability of a new tobacco product. Future, larger actual use studies will provide important evidence supporting the role that alternatives to combustible cigarettes may play in smoking reduction and/or cessation and lowering the population health burden of tobacco and nicotine-containing products.

Recruiting Fathers for Parenting Research: An Evaluation of Eight Recruitment Methods and an Exploration of Fathers' Motivations for Participation

Objective

We evaluated eight recruitment methods (Craigslist, Facebook ads, Google AdWords, in-person, newspaper, parenting magazines, ResearchMatch, and direct mailing) in terms of their ability to accrue fathers of 3- to 7-year-old children into a laboratory-based behavioral trial for parents. The trial was related to child obesity risk and parental health behaviors.

Design

Each recruitment method was implemented such that half its occurrences advertised for fathers only, and half advertised for mothers and fathers. Methods were evaluated in terms of number of fathers recruited, cost- and time-efficiency, response rates, and demographic characteristics of individuals recruited. We also assessed fathers' and mothers' motivations for participating in the study. 101 fathers and 260 mothers were recruited.

Results

Father-targeted ads were essential for father recruitment; 79% of accruals from father-targeted ads were male, whereas only 14% of accruals from parent-targeted ads were male. Craigslist, ResearchMatch, and Facebook ads were the most cost-efficient for accruing fathers. A greater proportion of fathers was motivated by increasing fathers' representation in research (16%) compared to mothers who wished to increase mothers' representation in research (5.4%). Similar proportions of fathers and mothers were motivated by improving their parenting knowledge and improving their child's health.

Conclusions

Future researchers should employ father-targeted recruitment materials (rather than parent-targeted) that capitalize on fathers' unique motivations for participating in research.

"Scary and Effective, Definitely Pushes Me to Quit Smoking": Developing Waterpipe Pictorial Health Warnings Targeting Young Adults in Lebanon

INTRODUCTION

Waterpipe (WP) smoking is the leading tobacco use method among young adults in Lebanon. WP use is harmful, yet misperceptions about its safety exist. Implementing pictorial health warning labels (HWLs) on WP products is a promising strategy to correct this misperception. This study aimed to culturally adapt a set of 12 pictorial HWLs recently developed by an international expert panel to young adults in Lebanon. HWLs were grouped into four themes: WP health risks, WP harm to others, WP-specific harms, and WP harm compared to cigarettes.

AIMS AND METHODS

We conducted nine focus groups among WP smokers and nonsmokers (N = 77; 52% females; age 18-34 years) to explore participants' perceptions of the developed HWLs on attention, reaction (fear, avoidance), effectiveness (harm perception), and improvement (design/content, relatedness). Sessions were audio-taped, transcribed verbatim, and analyzed using directed qualitative content analysis.

RESULTS

Emotionally provocative warnings were perceived as most effective, while symbolic and abstract warnings were found not believable. Warnings depicting visible bodily health effects and harm to babies seemed most promising. Participants were generally skeptical about Theme 4 because it might encourage switching to cigarettes. For cultural adaptation, participants recommended using shorter text with affirmative phrases, increasing the picture's size and improving their quality, adding the WP device picture to enhance HWLs' relatability, and develop testimonial messages that depict real people and stories.

CONCLUSIONS

Results will provide Lebanon and perhaps other countries in the Eastern Mediterranean Region with evidence-based HWLs that they can further develop, test, and implement within their specific culture.

IMPLICATIONS

Results provide Lebanon with evidence-based WP-specific pictorial HWLs that can be further developed and tested. HWLs provoking negative affect, with visible health consequences, and depicting harm to babies are promising. Participants recommended using definitive scientific claims presenting the health risks in numerical form. However, this needs to be balanced against protecting the credibility of HWLs scientifically and legally. Increasing the HWLs size and adding the WP device picture to the HWLs can enhance their relatability. Further research can help address some questions raised by this study, such as the potential of testimonial warnings that depict real people.

Recruiting racially and ethnically diverse smokers seeking treatment: Lessons learned from a smoking cessation randomized clinical trial

INTRODUCTION

Recruiting racial/ethnic minorities in smoking cessation trials is a priority. This study described lessons learned from recruiting a diverse sample of African American, White, and Hispanic/Latinx smokers in a smoking cessation trial.

METHODS

We implemented a 42-month recruitment campaign utilizing reactive (e.g., word-of-mouth, newspaper, radio, online ads, flyers, community partnerships) and proactive (e.g., direct invitations) strategies. We included 821 participants in the analysis. We described our recruitment strategies' implementation, their enrollment yield and rate (number enrolled/number screened) by race/ethnicity, and direct cost-per-participant (CPP: total cost/number of enrolled) for paid strategies.

RESULTS

Enrollment yields were higher using reactive strategies than proactive strategies (94.3% vs. 5.7%). The top source of enrollment was word-of-mouth among African Americans (36%) and Whites (44%), and flyers among Hispanics/Latinxs (34%). Proactive recruitment, word-of-mouth, and flyers were more successful among African Americans than other groups. Newspaper and online ads were more successful among Hispanics/Latinxs than other groups (P < .05). Word-of-mouth was cost-free and yielded 23.1% of enrollment. The most economic method among paid strategies was flyer distribution (CPP = $47.6; yield 17.5%), followed by newspaper ($194.7; 23.7%) and online advertisements ($264.6; 24.0%). Radio and television ads were the most expensive and produced the least participant yield ($4,755.6; 0.8%).

CONCLUSION

Recruiting racially/ethnically diverse samples into smoking cessation clinical trials requires implementing multiple strategies and adjusting these strategies based on their enrollment yield and cost. Word-of-mouth, flyers, and newspaper and online ads were more successful among racial/ethnic minorities. Flyers and newspaper ads were the most economic methods for recruitment.

Adapting Peer Researcher Facilitated Strategies to Recruit People Receiving Mental Health Services to a Tobacco Treatment Trial

INTRODUCTION

One of the most challenging aspects of conducting intervention trials among people who experience severe mental illness (SMI) and who smoke tobacco, is recruitment. In our parent "QuitLink" randomized controlled trial (RCT), slower than expected peer researcher facilitated recruitment, along with the impact of COVID-19 pandemic restrictions, necessitated an adaptive recruitment response. The objectives of the present study were to: (i) describe adaptive peer researcher facilitated recruitment strategies; (ii) explore the effectiveness of these strategies; (iii) investigate whether recruitment strategies reached different subgroups of participants; and (iv) examine the costs and resources required for implementing these strategies. Finally, we offer experience-based lessons in a Peer Researcher Commentary.

METHODS

People were included in the RCT if they smoked at least 10 cigarettes a day and were accessing mental health support from the project's two partnering mental health organizations in Victoria, Australia. The majority of people accessing these services will have been diagnosed with SMI. Recruitment occurred over 2 years. We began with peer facilitated recruitment strategies delivered face-to-face, then replaced this with direct mail postcards followed by telephone contact. In the final 4 months of the study, we began online recruitment, broadening it to people who smoked and were accessing support or treatment (including from general practitioners) for mental health and/or alcohol or other drug problems, anywhere in the state of Victoria. Differences between recruitment strategies on key participant variables were assessed. We calculated the average cost per enrolee of the different recruitment approaches.

RESULTS

Only 109 people were recruited from a target of 382: 29 via face-to-face (March 2019 to April 2020), 66 from postcards (May 2020 to November 2020), and 14 from online (November to December 2020 and January to March 2021) strategies. Reflecting our initial focus on recruiting from supported independent living accommodation facilities, participants recruited face-to-face were significantly more likely to be living in partially or fully supported independent living (n = 29, <0.001), but the samples were otherwise similar. After the initial investment in training and equipping peer researchers, the average cost of recruitment was AU$1,182 per participant-~US$850. Face-to-face recruitment was the most expensive approach and postcard recruitment the least (AU$1,648 and AU$928 per participant).

DISCUSSION

Peer researcher facilitated recruitment into a tobacco treatment trial was difficult and expensive. Widely dispersed services and COVID-19 restrictions necessitated non-face-to-face recruitment strategies, such as direct mail postcards, which improved recruitment and may be worthy of further research.

CLINICAL TRIAL REGISTRATION

The trial is registered with ANZCTR (www.anzctr.org.au): ACTRN12619000244101 prior to the accrual of the first participant and updated regularly as per registry guidelines. The trial sponsor was the University of Newcastle, NSW, Australia.

Barriers and facilitators for clinical trial participation of underrepresented and non-underrepresented fibromyalgia patients: A cross-sectional internet survey

BACKGROUND

There is a need of well-powered randomized clinical trials in fibromyalgia. However, challenges for recruitment are presented. This study aims to describe and assess the perception of barriers and facilitators and the associated factors for the participation of underrepresented and non-underrepresented fibromyalgia patients.

METHODS

We performed an online survey through REDCap (Research Electronic Data Capture) targeting fibromyalgia patients from April 7 to July 3, 2020 during the COVID-19 stay home mandate and it was restricted to the United States of America. We described and compared the survey characteristics between underrepresented and non-underrepresented participants, and we performed logistic regression models to assess the associated factors with clinical trial participation.

RESULTS

In total, 481 completed the survey including 168 underrepresented fibromyalgia patients. Only (1) 11.09 % reported previous participation in clinical trials and the significant perceived barriers were investigator-related (lack of friendliness of research staff and the opportunity to receive the results) and center-related (privacy and confidentiality policies, and the institution's reputation); (2) the participation rate and perceived barriers and facilitators were similar between underrepresented and non-underrepresented patients; and was positively associated with low income, higher age, and clinical trial awareness from their physician; and negatively associated with the perception of investigator-related barriers; and (4) for the underrepresented population, the presence of emotional support.

CONCLUSION

Our findings suggest low rates of participation, regardless of underrepresented population status. Strategies as involving their physician as liaison to increase the awareness of clinical trials, as well as improving patient-researcher communication should be considered in this population.

Predictors of Enrollment of Older Smokers in Six Smoking Cessation Trials in the Lung Cancer Screening Setting: The Smoking Cessation at Lung Examination (SCALE) Collaboration

SIGNIFICANCE

Increased rates of smoking cessation will be essential to maximize the population benefit of low-dose CT screening for lung cancer. The NCI's Smoking Cessation at Lung Examination (SCALE) Collaboration includes eight randomized trials, each assessing evidence-based interventions among smokers undergoing lung cancer screening (LCS). We examined predictors of trial enrollment to improve future outreach efforts for cessation interventions offered to older smokers in this and other clinical settings.

METHODS

We included the six SCALE trials that randomized individual participants. We assessed demographics, intervention modalities, LCS site and trial administration characteristics, and reasons for declining.

RESULTS

Of 6,285 trial- and LCS-eligible individuals, 3,897 (62%) declined and 2,388 (38%) enrolled. In multivariable logistic regression analyses, Blacks had higher enrollment rates (OR 1.5, 95% CI 1.2,1.8) compared to Whites. Compared to 'NRT Only' trials, those approached for 'NRT+prescription medication' trials had higher odds of enrollment (OR 6.1, 95% CI 4.7,7.9). Regarding enrollment methods, trials using 'Phone+In Person' methods had higher odds of enrollment (OR 1.6, 95% CI 1.2,1.9) compared to trials using 'Phone Only' methods. Some of the reasons for declining enrollment included 'too busy' (36.6%), 'not ready to quit' (8.2%), 'not interested in research' (7.7%), and 'not interested in the intervention offered' (6.2%).

CONCLUSION

Enrolling smokers in cessation interventions in the LCS setting is a major priority that requires multiple enrollment and intervention modalities. Barriers to enrollment provide insights that can be addressed and applied to future cessation interventions to improve implementation in LCS and other clinical settings with older smokers.

IMPLICATIONS

We explored enrollment rates and reasons for declining across six smoking cessation trials in the lung cancer screening setting. Offering multiple accrual methods and pharmacotherapy options predicted increased enrollment across trials. Enrollment rates were also greater among Blacks compared to Whites. The findings offer practical information for the implementation of cessation trials and interventions in the lung cancer screening context and other clinical settings, regarding intervention modalities that may be most appealing to older, long-term smokers.

A digital behaviour change intervention to increase booking and attendance at Stop Smoking Services: the MyWay feasibility RCT

Background

Smoking remains a leading cause of illness and preventable death. NHS Stop Smoking Services increase quitting, but, as access is in decline, cost-effective interventions are needed that promote these services. StopApp™ (Coventry University, Coventry, UK) is designed to increase booking and attendance at Stop Smoking Services.

Design

A two-arm feasibility randomised controlled trial of StopApp (intervention) compared with standard promotion and referral to Stop Smoking Services (control) was conducted to assess recruitment, attrition and health equity of the design, alongside health economic and qualitative process evaluations.

Setting

Smokers recruited via general practitioners, community settings and social media.

Participants

Smokers aged ≥ 16 years were recruited in one local authority. Participants had to live or work within the local authority area, and there was a recruitment target of 120 participants.

Interventions

StopApp to increase booking and attendance at Stop Smoking Services.

Main outcome measures

Participants completed baseline measures and follow-up at 2 months post randomisation entirely online. Objective data on the use of Stop Smoking Services were collected from participating Stop Smoking Services, and age groups, sex, ethnicity and socioeconomic status in baseline recruits and follow-up completers/non-completers were assessed for equity.

Results

Eligible participants (n = 123) were recruited over 116 days, with good representation of lower socioeconomic status groups; black, Asian and minority ethnic groups; and all age groups. Demographic profiles of follow-up completers and non-completers were broadly similar. The attrition rate was 51.2%, with loss to follow-up lowest in the social media setting (n = 24/61; 39.3%) and highest in the general practitioner setting (n = 21/26; 80.8%). Most measures had < 5% missing data. Social media represented the most effective and cost-efficient recruitment method. In a future, definitive, multisite trial with recruitment driven by social media, our data suggest that recruiting ≥ 1500 smokers over 12 months is feasible. Service data showed that five bookings for the Stop Smoking Services were scheduled using StopApp, of which two did not attend. Challenges with data access were identified. A further five participants in the intervention arm self-reported booking and accessing Stop Smoking Services outside StopApp compared with two control arm participants. Event rate calculations for the intervention were 8% (Stop Smoking Services data), 17% (including self-reports) and 3.5% from control arm self-reports. A conservative effect size of 6% is estimated for a definitive full trial. A sample size of 840 participants would be required to detect an effect for the primary outcome measure of booking a Stop Smoking Services appointment in a full randomised controlled trial. The process evaluation found that participants were satisfied with the research team contact, study methods and provision of e-vouchers. Staff interviews revealed positive and negative experiences of the trial and suggestions for improvements, including encouraging smokers to take part.

Conclusion

This feasibility randomised controlled trial found that, with recruitment driven wholly or mainly by social media, it is possible to recruit and retain sufficient smokers to assess the effectiveness and cost-effectiveness of StopApp. The study methods and measures were found to be acceptable and equitable, but accessing Stop Smoking Services data about booking, attendance and quit dates was a challenge. A full trial may be feasible if service data are accessible. This will require careful planning with data controllers and a targeted social media campaign for recruitment. Changes to some study measures are needed to avoid missing data, including implementation of a more intensive follow-up data collection process.

Future work

We plan a full, definitive randomised controlled trial if the concerns around data access can be resolved, with adaptations to the recruitment and retention strategy.

Limitations

Our trial had high attrition and problems with collecting Stop Smoking Services data, which resulted in a reliance on self-reporting.

Trial registration

Research Registry: 3995. The trial was registered on 18 April 2018.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 9, No. 5. See the NIHR Journals Library website for further project information.

Online Patient Recruitment in Clinical Trials: Systematic Review and Meta-Analysis

Background

Recruitment for clinical trials continues to be a challenge, as patient recruitment is the single biggest cause of trial delays. Around 80% of trials fail to meet the initial enrollment target and timeline, and these delays can result in lost revenue of as much as US $8 million per day for drug developing companies.

Objective

This study aimed to conduct a systematic review and meta-analysis examining the effectiveness of online recruitment of participants for clinical trials compared with traditional in-clinic/offline recruitment methods.

Methods

Data on recruitment rates (the average number of patients enrolled in the study per month and per day of active recruitment) and conversion rates (the percentage of participants screened who proceed to enroll into the clinical trial), as well as study characteristics and patient demographics were collected from the included studies. Differences in online and offline recruitment rates and conversion rates were examined using random effects models. Further, a nonparametric paired Wilcoxon test was used for additional analysis on the cost-effectiveness of online patient recruitment. All data analyses were conducted in R language, and P<.05 was considered significant.

Results

In total, 3861 articles were screened for inclusion. Of these, 61 studies were included in the review, and 23 of these were further included in the meta-analysis. We found online recruitment to be significantly more effective with respect to the recruitment rate for active days of recruitment, where 100% (7/7) of the studies included had a better online recruitment rate compared with offline recruitment (incidence rate ratio [IRR] 4.17, P=.04). When examining the entire recruitment period in months we found that 52% (12/23) of the studies had a better online recruitment rate compared with the offline recruitment rate (IRR 1.11, P=.71). For cost-effectiveness, we found that online recruitment had a significantly lower cost per enrollee compared with offline recruitment (US $72 vs US $199, P=.04). Finally, we found that 69% (9/13) of studies had significantly better offline conversion rates compared with online conversion rates (risk ratio 0.8, P=.02).

Conclusions

Targeting potential participants using online remedies is an effective approach for patient recruitment for clinical research. Online recruitment was both superior in regard to time efficiency and cost-effectiveness compared with offline recruitment. In contrast, offline recruitment outperformed online recruitment with respect to conversion rate.

Digital tools for the recruitment and retention of participants in randomised controlled trials: a systematic map

BACKGROUND

Recruiting and retaining participants in randomised controlled trials (RCTs) is challenging. Digital tools, such as social media, data mining, email or text-messaging, could improve recruitment or retention, but an overview of this research area is lacking. We aimed to systematically map the characteristics of digital recruitment and retention tools for RCTs, and the features of the comparative studies that have evaluated the effectiveness of these tools during the past 10 years.

METHODS

We searched Medline, Embase, other databases, the Internet, and relevant web sites in July 2018 to identify comparative studies of digital tools for recruiting and/or retaining participants in health RCTs. Two reviewers independently screened references against protocol-specified eligibility criteria. Included studies were coded by one reviewer with 20% checked by a second reviewer, using pre-defined keywords to describe characteristics of the studies, populations and digital tools evaluated.

RESULTS

We identified 9163 potentially relevant references, of which 104 articles reporting 105 comparative studies were included in the systematic map. The number of published studies on digital tools has doubled in the past decade, but most studies evaluated digital tools for recruitment rather than retention. The key health areas investigated were health promotion, cancers, circulatory system diseases and mental health. Few studies focussed on minority or under-served populations, and most studies were observational. The most frequently-studied digital tools were social media, Internet sites, email and tv/radio for recruitment; and email and text-messaging for retention. One quarter of the studies measured efficiency (cost per recruited or retained participant) but few studies have evaluated people's attitudes towards the use of digital tools.

CONCLUSIONS

This systematic map highlights a number of evidence gaps and may help stakeholders to identify and prioritise further research needs. In particular, there is a need for rigorous research on the efficiency of the digital tools and their impact on RCT participants and investigators, perhaps as studies-within-a-trial (SWAT) research. There is also a need for research into how digital tools may improve participant retention in RCTs which is currently underrepresented relative to recruitment research.

REGISTRATION

Not registered; based on a pre-specified protocol, peer-reviewed by the project's Advisory Board.

Trial marketing in the Pan-Canadian Early Detection of Lung Cancer Study

BACKGROUND

Recruitment to clinical trials is suboptimal, increasing costs, and delaying the potential implementation of clinical advances. Among other barriers, the lack of marketing experience among trialists may limit recruitment. In this observational study, in the context of the Pan-Canadian Early Detection of Lung Cancer Trial, we assessed the value of a motivational survey of study participants in planning a tailored advertising campaign and analysed the value of individual components of advertising in generating telephone calls to the study and recruited subjects.

METHODS

The Pan-Canadian Early Detection of Lung Cancer Trial was a single arm study assessing risk modelling for lung cancer screening by low-dose computed tomography scan and autofluorescence bronchoscopy. Individuals were recruited to eight sites across Canada without a central marketing plan. On contact with the study, individuals reported how they heard about the study according to a predefined list. One site, the Juravinski Cancer Centre, worked with a marketing expert to develop a survey to assess participant motivations, source of study awareness, and personal habits. The survey was used to develop a media campaign for recruitment. Media events were collected from all sites. The primary analysis assessed the number of telephone contacts and recruited subjects associated with various media factors. Individual print media characteristics were assessed for their effect on recruitment.

RESULTS

At all sites, 7059 individuals contacted the study, and 2537 were eligible and recruited. Among 52 individuals completing the Juravinski Cancer Centre survey, motivation included concern for personal risk of lung cancer (71%), followed by desire to contribute to a cure (67%), followed by personal knowledge of a person with lung cancer (50%). Most reported hearing of the study from the newspaper (58%) despite no print ad yet being distributed. With survey input, a newsprint campaign was executed. The number of media events varied by site (median: 13, range: 3-28). Among all recruits, 56.4% reported referral by newspaper followed by family/friend (14%). Telephone contacts and recruited subjects per event varied significantly by site, while unpaid media events appeared superior to paid events. Print media characteristics associated with increased telephone contacts and recruitment included use of a rational appeal (vs a mixed rational-emotional), less use of white space, and larger headline font.

CONCLUSION

A survey of trial candidates provides useful information regarding personal motivation, media use, and lifestyle. Unpaid media events appear superior in generating recruitment, while print media may be superior to radio and television in selecting eligible recruits. The utility of individual print media characteristics appears to differ from the commercial advertising literature. Further research on marketing in clinical trials is encouraged to improve recruitment ( ClinicalTrials.gov registration: NCT00751660, https://clinicaltrials.gov/ct2/show/NCT00751660 ).

Cost Per Participant Recruited From Rural and Remote Areas Into a Smoking Cessation Trial Via Online or Traditional Strategies: Observational Study

Background

Rural and remote residents are more likely to smoke than those who live in major cities; however, recruitment of research participants from rural and remote areas can be challenging. The cost per participant recruited from rural and remote areas via online (eg, social media) and traditional strategies (eg, print) has implications for researchers on how to allocate resources to maximize the number of participants recruited. Participant characteristics such as demographics, financial stress, mental health, and smoking-related factors may be associated with recruitment method (ie, online vs traditional), and so it is important to understand whether certain subgroups are more likely to be recruited via a particular strategy.

Objective

This study aimed to determine the cost per participant recruited and examine whether characteristics such as demographics, financial stress, mental health, and smoking-related factors may be associated with the recruitment method (ie, online vs traditional).

Methods

Participants were recruited into a randomized trial that provided smoking cessation support. Eligible participants were aged 18 years or older; used tobacco daily; had access to video communication software, internet, and telephone; had an email address; and lived in a rural or remote area of New South Wales, Australia. This study describes the natural (observed) experience of recruiting participants via online and traditional methods into a smoking cessation trial.

Results

Over 17 months, 655 participants were recruited into the smoking cessation trial. A total of 88.7% (581/655) of the participants were recruited via online methods. Moreover, 1.8% (12/655) of the participants were recruited from remote locations and none from very remote areas. The cost per participant recruited by the various online strategies ranged from Aus $7.29 (US $4.96, £4.09, and €4.43) for Gumtree, a local online classified website, to Aus $128.67 (US $87.63, £72.20, and €78.28) for email. The cost per participant recruited using traditional strategies ranged from Aus $0 (US $0, £0, and €0) for word of mouth to Aus $3990.84 (US $2757.67, £2227.85, and €2477.11) for telephone. Women had greater odds of being recruited via online methods than men (odds ratio 2.50, 95% CI 1.42-4.40). No other characteristics were associated with the recruitment method.

Conclusions

The cost per participant recruited via online and traditional strategies varied, with the range being smaller for online than traditional recruitment strategies. Women have greater odds of being recruited via online strategies into rural smoking cessation trials.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN12617000514303; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=372584&isReview=true

Website Analytics of a Google Ads Campaign for a Men's Mental Health Website: Comparative Analysis

BACKGROUND

Men with mental health and addictions problems seek information and help from health service providers and community support less often than women with such problems. Online health resources offer men rapid access to self-care recommendations and resources and anonymity; however, only a few websites are specifically developed for men. Headstrong - Taking Things Head-On was a community pharmacy and online health promotion initiative for men living with mental health and addictions problems. The Headstrong website was developed to offer a curated collection of print and online recommended resources (primarily self-help oriented) for depression, anxiety, insomnia, tobacco and alcohol use problems, and suicide. To increase awareness of the initiative and use of the website's content and resource recommendations, a Google Ads campaign was developed.

OBJECTIVE

This study aimed to compare user acquisition and behavior on the Headstrong website during and after a Google Ads campaign.

METHODS

The Google Ads campaign was launched on December 21, 2017, and run until February 28, 2018. Website analytics (acquisition of new users, behavior in terms of at-website actions and duration, devices used, and conversions [link-outs to recommended resources]) in a 30-day period during the campaign (January 26, 2018 to February 24, 2018) were compared to a similar 30-day period after the campaign (March 23, 2018 to April 21, 2018). A cost analysis of the ad campaign was also performed.

RESULTS

The ad campaign generated 3011 clicks and 4.5 million impressions in total. In addition, the campaign received 1311 website users during the 30-day period of the ad campaign as compared to 241 users during the 30-day period after the ad campaign (P<.001). Return visitor (17.7% vs 27.8%) and nonbounce (19.5% vs 39.8%) user rates as well as session duration (42 vs 102 seconds) and page views per session (1.4 vs 2.1) were lower during the ad campaign than after the campaign (P<.01 for all). The 30-day period of the ad campaign included 9 sessions with conversions initiated by an ad click. Paid and display ads accounted for 63% of the site traffic during the ad campaign, most of which came from mobile phone users. Desktops were the most-common device used after the ad campaign acquired the website via direct and organic searches primarily (92%). The estimated cost per session with one or more conversions was Can $54.69 and cost per conversion was Can $32.81.

CONCLUSIONS

A Google Ads campaign designed to direct men to the Headstrong website increased the number of user visits by more than five-fold. However, engagement by users responding to the ad campaign was substantially lower than that by users who visited the website via other acquisition methods, possibly reflecting the nonspecific online targeting of men by the ad campaign. General targeting of men online to promote men's mental health appears to have limited value.

Obtaining contextually relevant geographic data using Facebook recruitment in public health studies

INTRODUCTION

Online participant recruitment for public health research studies has increased dramatically in recent years, particularly as traditional recruitment strategies have waned in efficiency. The emergence of e-epidemiology offers possibilities for reaching understudied populations as well as conducting large-scale studies.

METHODS

We conducted a cross-sectional survey focused on self-reported neighborhood characteristics, perceived stress, and feasibility of obtaining work/residential addresses via online recruitment in St. Louis, Missouri, USA from February 2017 to December 2017. We report the process of using Facebook recruitment and demonstrate how this strategy can enhance collection of geospatial data to better understand context and spatial patterns of disease.

RESULTS

A total of 425 participants were recruited via Facebook advertisements. All participants reported their residential and work ZIP codes, though only 64.7% and 45.6% provided their complete residential and work street addresses, respectively. Those who reported their complete residential street addresses were more likely to be female (69.8% vs. 56.1% of males, χ² = 7.89, 1 df, p = 0.005), though no differences were observed by race, age, or employment status.

DISCUSSION

These findings indicate that valuable location data can be successfully collected via Facebook recruitment - data that could potentially include residential history or prospective follow-up time or be combined with other emerging technologies for geographic data in order to better understand the context and the effects of place on health outcomes.

CONCLUSIONS

Facebook recruitment may be an underutilized resource for obtaining accurate geospatial and contextually relevant health data and should be considered as a means for finding participants due to the cost-effectiveness, efficiency and flexibility of this recruitment approach.

Recruitment Strategies and Costs Associated With Enrolling People With Insomnia and High Blood Pressure Into an Online Behavioral Sleep Intervention: A Single-Site Pilot Study

BACKGROUND

Recruitment in clinical research is a common challenge and source of study failure. The reporting of recruitment methods and costs in hypertension trials is limited especially for smaller, single-site trials, online intervention trials, and trials using newer online recruitment strategies.

OBJECTIVE

The aims of this study are to describe and examine the feasibility of newer online-e-mail recruitment strategies and traditional recruitment strategies used to enroll participants with insomnia and high blood pressure into an online behavioral sleep intervention study (Sleeping for Heart Health).

METHODS

The 16 online-e-mail-based and traditional recruitment strategies used are described. Recruitment strategy feasibility was examined by study interest and enrollee yields, conversion rates, and costs (direct, remuneration, labor, and cost per enrollee).

RESULTS

From August 2014 to October 2015, 183 people were screened and 58 (31.7%) enrolled in the study (51.1 ± 12.9 years, 63.8% female, 72.4% African American, 136 ± 12/88 ± 7 mm Hg, 87.9% self-reported hypertension, 67.2% self-reported antihypertensive medication use). The recruitment strategies yielding the highest enrollees were the university hospital phone waiting message system (25.4%), Craigslist (22.4%), and flyers (20.3%) at a per enrollee cost of $42.84, $98.90, and $128.27, respectively. The university hospital phone waiting message system (55.6%) and flyers (54.5%) had the highest interested participant to enrolled participant conversion rate of all recruitment strategies.

CONCLUSION

Approximately 70% of all enrolled participants were recruited from the university hospital phone waiting message system, Craigslist, or flyers. Given the recruitment challenges that most researchers face, we encourage the documenting, assessing, and reporting of detailed recruitment strategies and associated recruitment costs so that other researchers may benefit.

Using Facebook to Recruit Parents to Participate in a Family Program to Prevent Teen Drug Use

Despite strong evidence that family programs are effective in preventing adolescent substance use, recruiting parents to participate in such programs remains a persistent challenge. This study explored the feasibility of using Facebook to recruit parents of middle school students to a self-directed family program to prevent adolescent drug use. The study used paid Facebook ads aiming to recruit 100 parents in Washington and Colorado using marijuana- or parenting-focused messages. All ad-recruited parents were also invited to refer others in order to compare Facebook recruitment to web-based respondent-driven sampling. Despite offering a $15 incentive for each successfully referred participant, the majority of the screened (70.4%) and eligible (65.1%) parents were recruited through Facebook ads. Yet, eligibility and consent rates were significantly higher among referred (76.6 and 57.3%, respectively) than Facebook-recruited parents (60.0 and 36.6%, respectively). Click-through rates on Facebook were higher for marijuana-focused than parenting-focused ads (0.72 and 0.65%, respectively). The final sample (54% Facebook-recruited) consisted of 103 demographically homogeneous parents (female, educated, non-Hispanic White, and mostly from Washington). Although Facebook was an effective and efficient method to recruit parents to a study with equal to better cost-effectiveness than traditional recruitment strategies, the promise of social media to reach a diverse population was not realized. Additional approaches to Facebook recruitment are needed to reach diverse samples in real-world settings and increase public health impact of family programs.

Childhood Sexual Abuse, Attachments in Childhood and Adulthood, and Coercive Sexual Behaviors in Community Males

Associations between self-reported coercive sexual behavior against adult females, childhood sexual abuse (CSA), and child-parent attachment styles, as well as attachment with adult romantic partners, were examined among 176 adult community males. Attachment style with each parent and with romantic partners was also investigated as a potential moderator. Using hierarchical multiple regression analysis, avoidant attachment with mothers in childhood (and also with fathers, in a second model) accounted for a significant amount of the variance in coercive sexual behavior controlling for scores on anxious ambivalent and disorganized/disoriented attachment scales, as predicted. Similarly, in a third model, avoidance attachment in adulthood was a significant predictor of coercive sexual behavior controlling for scores on the anxiety attachment in adulthood scale. These main effects for avoidant and avoidance attachment were not statistically significant when CSA and control variables (other types of childhood adversity, aggression, antisociality, and response bias) were added in each of the models. But the interaction between scales for CSA and avoidance attachment in adulthood was significant, demonstrating incremental validity in a final step, consistent with a hypothesized moderating function for attachment in adulthood. The correlation between CSA and coercive sexual behavior was .60 for those with the highest third of avoidance attachment scores (i.e., the most insecurely attached on this scale), .24 for those with scores in the middle range on the scale, and .01 for those with the lowest third of avoidance attachment scores (i.e., the most securely attached). Implications for study design and theory were discussed.

Effectiveness and Cost-effectiveness of School-based Dissemination Strategies of an Internet-based Program for the Prevention and Early Intervention in Eating Disorders: A Randomized Trial

Only little is known about costs and effects (i.e., success) of dissemination strategies, although cost-effective dissemination strategies are crucial for the transfer of interventions into routine care. This study investigates the effects and cost-effectiveness of five school-based dissemination strategies for an Internet-based intervention for the prevention and early intervention of eating disorders. Three-hundred ninety-five schools were randomly assigned to one of five dissemination strategies. Strategies varied with respect to intensity from only sending advertisement materials and asking the school to distribute them among students to organizing presentations and workshops at schools. Effects were defined as the number of page visits, the number of screenings conducted, and the number of registrations to the Internet-based intervention. More expensive strategies proved to be more cost-effective. Cost per page visit ranged from 2.83€ (introductory presentation plus workshop) to 20.37€ (dissemination by student representatives/peers). Costs per screening ranged from 3.30€ (introductory presentation plus workshop) to 75.66€ (dissemination by student representatives/peers), and costs per registration ranged from 6.86€ (introductory presentation plus workshop) to 431.10€ (advertisement materials only). Dissemination of an Internet-based intervention for prevention and early intervention is challenging and expensive. More intense, expensive strategies with personal contact proved to be more cost-effective. The combination of an introductory presentation on eating disorders and a workshop in the high school was most effective and had the best cost-effectiveness ratio. The sole distribution of advertisement materials attracted hardly any participants to the Internet-based program.

Recruiting Diverse Smokers: Enrollment Yields and Cost

To help tobacco control research better include vulnerable populations, we sought to identify effective ways to recruit diverse smokers. In 2014–2015, we recruited 2149 adult cigarette smokers in California and North Carolina, United States, to participate in a randomized trial of pictorial cigarette pack warnings. The most effective means of recruiting smokers were the classified advertising website Craigslist (28% of participants), word of mouth (23%), Facebook (16%), and flyers or postcards (14%). Low-income and African American smokers were more likely to respond to interpersonal contact (including staff in-person recruitment and word of mouth) than were high-income and non-African American smokers (all p < 0.05). Hispanic and gay, lesbian, and bisexual smokers were more likely to be recruited by Craigslist than non-Hispanic and straight smokers (both p < 0.05). Of the recruitment methods requiring cost, the cheapest was Craigslist ($3–7 per smoker). The most expensive methods were newspaper ads in California ($375 per smoker) and staff in-person recruiting in North Carolina ($180 per smoker). Successfully recruiting diverse smokers requires using multiple methods including interpersonal, online, and other media. Craigslist and word of mouth are especially useful and low-cost ways to recruit diverse smokers.

Recruitment Strategies of Indian Men Who Have Sex with Men in the State of Maharashtra Into an Online Survey

In this manuscript, we report lessons learned from our efforts to recruit Indian men and transgender women/hijras who have sex with men into an online cross sectional study. Between September 2013 and May 2014, we implemented a seven-phased recruitment strategy that included the use of online and offline strategies to enroll a total of 449 participants into an online survey about recent sexual behavior and various psychosocial measures. The phases were implemented sequentially and cost-per-eligible participant was calculated. Using social media and collaborating with organizers of community events proved the most effective strategies for recruiting Indian MSM into online research.

Text Messaging-Based Interventions for Smoking Cessation: A Systematic Review and Meta-Analysis

BACKGROUND

Tobacco use is one of the leading preventable global health problems producing nearly 6 million smoking-related deaths per year. Interventions delivered via text messaging (short message service, SMS) may increase access to educational and support services that promote smoking cessation across diverse populations.

OBJECTIVE

The purpose of this meta-analysis is to (1) evaluate the efficacy of text messaging interventions on smoking outcomes, (2) determine the robustness of the evidence, and (3) identify moderators of intervention efficacy.

METHODS

Electronic bibliographic databases were searched for records with relevant key terms. Studies were included if they used a randomized controlled trial (RCT) to examine a text messaging intervention focusing on smoking cessation. Raters coded sample and design characteristics, and intervention content. Summary effect sizes, using random-effects models, were calculated and potential moderators were examined.

RESULTS

The meta-analysis included 20 manuscripts with 22 interventions (N=15,593; 8128 (54%) women; mean age=29) from 10 countries. Smokers who received a text messaging intervention were more likely to abstain from smoking relative to controls across a number of measures of smoking abstinence including 7-day point prevalence (odds ratio (OR)=1.38, 95% confidence interval (CI)=1.22, 1.55, k=16) and continuous abstinence (OR=1.63, 95% CI=1.19, 2.24, k=7). Text messaging interventions were also more successful in reducing cigarette consumption relative to controls (d+=0.14, 95% CI=0.05, 0.23, k=9). The effect size estimates were biased when participants who were lost to follow-up were excluded from the analyses. Cumulative meta-analysis using the 18 studies (k=19) measuring abstinence revealed that the benefits of using text message interventions were established only after only five RCTs (k=5) involving 8383 smokers (OR=1.39, 95% CI=1.15, 1.67, P<.001). The inclusion of the subsequent 13 RCTs (k=14) with 6870 smokers did not change the established efficacy of text message interventions for smoking abstinence (OR=1.37, 95% CI=1.25, 1.51, P<.001). Smoking abstinence rates were stronger when text messaging interventions (1) were conducted in Asia, North America, or Europe, (2) sampled fewer women, and (3) recruited participants via the Internet.

CONCLUSIONS

The evidence for the efficacy of text messaging interventions to reduce smoking behavior is well-established. Using text messaging to support quitting behavior, and ultimately long-term smoking abstinence, should be a public health priority.

Effect of nicotine replacement therapy on quitting by young adults in a trial comparing cessation services

CONTEXT

Young adult smokers have the highest smoking prevalence among all US age groups but are least likely to use evidence-based cessation counseling or medication to quit.

OBJECTIVE

Use and effectiveness of nicotine patch were explored in a randomized trial evaluating smoking cessation interventions with this population.

PARTICIPANTS

Smokers aged 18 to 30 (n = 3094) were recruited through online and off-line methods and from telephone quit lines and analyzed.

DESIGN

Smokers were enrolled in a pretest-posttest trial, and randomized to 1 of 3 cessation services.

SETTING

Trial delivering counseling services by self-help booklet, telephone quit lines, or online expert system in the 48 continental United States.

INTERVENTION

Smokers could request a free 2-week course of nicotine replacement therapy (NRT) patches from the project.

MAIN OUTCOME MEASURE

Follow-up surveys at 12 and 26 weeks assessed smoking abstinence, use of NRT, counseling, and other cessation medications, and smoking-related variables.

RESULTS

Overall, 69.0% of smokers reported using NRT (M = 3.2 weeks) at 12 weeks and 74.8% (M = 3.3 weeks) at 26 weeks. More smokers who were sent the free nicotine patches (n = 1695; 54.8%) reported using NRT than those who did not receive them (12 weeks: 84.3% vs 41.9%, P < .001; 26 weeks: 87.6% vs 51.1%, P < .001). The use of NRT was associated with greater smoking abstinence at 12 weeks (P < .001) and 26 weeks (P < .05), especially if used for more than 2 weeks (P < .001). Smokers assigned to a self-help booklet or cessation Web site and heavier smokers were most likely to use NRT (P < .05), whereas those reporting marijuana use and binge drinking used NRT less (P < .05).

CONCLUSIONS

Many young adults were willing to try NRT, and it appeared to help them quit in the context of community-based cessation services. Strategies should be developed to make NRT available to this age group and support them in using it to prevent lifelong smoking.

Recruitment Strategies of Methamphetamine-Using Men Who Have Sex with Men into an Online Survey

Recruiting hidden populations into online research remains challenging. In this manuscript, we report lessons learned from our efforts to recruit methamphetamine-using men who have sex with men. Between July and October 2012, we implemented a four-phase recruitment strategy to enroll a total of 343 methamphetamine-using MSM into an online survey about recent substance use, sexual behavior, and various psychosocial measures. The four phases were implemented sequentially. During phase one, we placed advertisements on mobile applications, and during phase two, we placed advertisements on traditional websites formatted for browsers. During phase three, we used e-mail to initiate snowball recruitment, and during phase four, we used social media for snowball recruitment. Advertisements on mobile devices and websites formatted for browsers proved to be expensive options and resulted in few eligible participants. Our attempts to initiate a snowball through e-mail also proved unsuccessful. The majority (n=320) of observations in our final dataset came from our use of social media. However, participant fraud was a concern, requiring us to implement a strong participant verification protocol. For maximum recruitment and cost-effectiveness, researchers should use social media for recruitment provided they employ strong participant verification protocols.

Using Google Adwords to recruit family carers of people with dementia

AIM

Online advertising is a new frontier in research recruitment and Google Adwords (GA) is one method of online advertising. Only a handful of studies, however, have described its cost and effectiveness and none have focused on older adults. The aim of this paper is to describe a GA campaign used to recruit family carers of people with dementia and provide insight for researchers planning to use GA to recruit other older adults.

METHOD

A GA campaign was used to recruit family carers of people with dementia to a cross-sectional study of wellbeing.

RESULTS

The ads were viewed more than 450,000 times in a six-week period, but only 49 surveys were completed, at a cost of $122 per survey.

CONCLUSION

GA has promise, but much remains to be understood about how to maximize its potential in ageing research. Recommendations for the design of future GA campaigns are provided.

Internet-based recruitment to a depression prevention intervention: lessons from the Mood Memos study

Background

Recruiting participants to randomized controlled trials of health interventions can be very difficult. Internet-based recruitment is becoming an increasingly important mode of recruitment, yet there are few detailed accounts of experiences recruiting participants to mental health interventions.

Objective

To report on our experience with Internet-based recruitment to an online depression prevention intervention and pass on lessons we learned.

Methods

Participants were recruited to the Mood Memos study, an online preventive depression intervention, purely through Internet-based sources. The study was targeted to adults with subthreshold depression symptoms from several English-speaking countries. A variety of online recruitment sources were trialed, including search engine advertising (Google, Yahoo!, Bing), Facebook advertising, posts in forums and online noticeboards, and promotion through relevant websites and email newsletters of mental health organizations.

Results

The study website received visits from 94,808 individuals over the 14-month recruitment period. The recruitment target was reached with 1699 individuals signing up to the randomized controlled trial and 1326 fully enrolling. Most visitors arrived via Google advertising, which promoted a depression-screening questionnaire. Google advertising accounted for nearly half of the total participants who signed up to the study, at an average cost of AUD $12 per participant. Promoting the study through trustworthy organizations and websites known to participants was also effective. Recruitment techniques that were less effective were contacting forums, email groups, and community noticeboards.

Conclusions

Several techniques, including Google advertising, were successful in recruiting participants to a trial evaluating an online depression intervention. Results suggest that Internet-based recruitment to mental health interventions is feasible and can be relatively affordable.

Trial Registration

ACTRN12609000925246