Barriers and Strategies in Recruitment for Bariatric Surgery Research

Abstract

Bariatric surgery patients present unique challenges for research recruitment. These include the stigma of obesity, sensitive psychosocial issues that may accompany obesity, and the many requirements of insurers before surgery is approved. Yet, little guidance is found in the literature on ways to improve recruitment success for bariatric surgery patients specifically. The purpose of this article is to describe the strategies we developed to overcome anticipated and unanticipated barriers to recruiting bariatric surgery patients for a prospective pilot study. First, we review the literature on barriers to recruitment and strategies to improve recruitment for clinical research projects in general. Pertinent barriers include fear of emotional distress, practical and logistical concerns for data collection, issues related to research regulations, and clinician attitudes regarding the study. Second, we demonstrate the ways in which successful strategies from the literature were incorporated into our recruitment plan. To help devise the recruitment plan, we categorized successful strategies into six recruitment steps that comprised the recruitment process for our pilot study. Third, we describe the ways in which our recruitment plan evolved to address unexpected challenges that emerged despite our systematic approach. We were able to complete the pilot study and maintain its integrity, but our initial goal of completing the study within a year was compromised. The information from this experience will help fill a gap in the literature, and can be used to improve the recruitment efficiency of bariatric surgery nurses and researchers who are involved in clinical research with bariatric surgery patients.

Introduction

Bariatric surgery is evolving in a positive direction, as demonstrated by current data on its safety and effectiveness for weight loss.¹ Nonetheless, more research is needed on factors that affect the outcomes of bariatric surgery. Our multidisciplinary team developed a prospective pilot study on the interplay of two factors that may affect bariatric surgery outcomes: a history of childhood sexual abuse (CSA) and hypothalamic-pituitary-adrenal (HPA) axis regulation. The rationale for the study was twofold. First, epidemiological studies of the past decade indicate CSA increases risk for obesity in adulthood.^2–6 As many as 32% of bariatric surgery patients report a history of CSA.^7,8 Second, the HPA axis may be a mechanism that links CSA with increased risk for obesity in adulthood; HPA axis hormones are involved in both the stress response and weight homeostasis.^9,10 We hypothesized that alterations in HPA axis regulation due to the stress of CSA may contribute not only to adult obesity, but also to the outcomes of bariatric surgery.

The setting for recruitment was a Midwestern academic health center that has a long-standing bariatric surgery program and is a Bariatric Center of Excellence. The majority of patients were covered by Medicare, Medicaid, and private insurance, with a few being self-pay. Both public and private insurers required evidence of weight loss before surgery was approved. Data were collected before surgery (baseline) and at 3 and 6 months post-surgery. CSA was measured by a self-administered questionnaire during baseline data collection. We narrowed our focus to women for the pilot study because this detailed questionnaire on CSA was specifically designed for women.¹¹ The measure of HPA axis regulation was diurnal cortisol secretion. Participants were asked to self-collect nine saliva samples for cortisol levels every day for three consecutive days during each data collection point. Bariatric surgery outcome variables included percent of excess weight loss and quality of life.

Using methods for determining pilot sample size described by Hertzog,¹² we determined that 20 participants would provide acceptable confidence levels for the feasibility data to be collected. We set a goal to complete the study within one year. This goal was based on (a) the weekly number of first bariatric surgery clinic visits by females at the academic health center (about three to seven per week) and (b) the prevalence of CSA among bariatric patients as documented in the literature (see above). If approximately 20 female patients were seen for their first bariatric surgery visit per month, about five were likely to have experienced CSA. Therefore, we figured that approximately 30 potentially eligible patients would have their first bariatric surgery visit during the first 6 months of the pilot study. A recruitment rate of 66% would yield the 20 needed participants within six months and allow us to complete prospective data collection within 1 year.

We anticipated that recruitment for our pilot study would be challenging due to (a) the double stigma of obesity and CSA and (b) the rigorous data collection protocol required for our measure of HPA axis regulation. However, we found little to guide us in the literature about the specific challenges of recruiting bariatric surgery patients for clinical research. Further, our initial recruiting plan and early recruitment efforts were hindered by barriers that we did not anticipate, resulting in the need to develop strategies to move the recruitment forward. The purpose of this article is to describe the strategies developed for this pilot study to overcome anticipated and unanticipated barriers to recruiting bariatric surgery patients for clinical research. In the Literature Review section, we synthesize barriers and strategies in recruitment for clinical research in general that pertained to our specific study. Next, in the Methods and Materials section, we illustrate the ways in which we used this literature to improve the chances of successful recruitment for our targeted population. Finally, in the Results section, we describe the challenges we encountered during our recruitment efforts, and identify strategies we developed to surmount these unexpected challenges to successfully obtain the feasibility data we needed for our pilot study.

Literature Review

A literature review on barriers to recruitment for clinical research in general helped us identify and clarify potential barriers for the pilot study. The literature revealed four main themes that were particularly relevant: (1) fear of being a research “subject,”^13–21 (2) practical and logistical concerns,^{14–16,18,21–23} (3) regulations imposed by Institutional Review Boards (IRBs) and the Health Insurance Portability and Accountability Act (HIPAA),^19,23–26 and (4) clinician and clinic staff attitudes regarding the study.^22,23,26,27

Fear of being a research subject is not limited to research that poses a risk for physical harm. In particular, fear of emotional distress can be a deterrent to research participation when the topic addressed is sensitive or stigmatizing.^13–15 Practical and logistical concerns on the part of potential participants were expected, given we would be requesting a total of 81 saliva samples from each participant over the course of the study. In addition, IRB and HIPAA regulations would require the recruiters to approach patients only after being invited to do so by the patient because they were not clinic employees. Therefore, clinicians and clinic staff members would be relied upon to introduce the study to patients after their clinic visit and ask them if they wanted to visit with a recruiter. Their positive opinion of the study would be essential.

Given the anticipated barriers, we understood that our recruitment strategies needed to be solid. Therefore, we next reviewed the literature for successful strategies for recruitment. Based on the review, we categorized the successful strategies into six recruitment steps applicable to our pilot study (see Table 1). Because recruitment is a process, an inherent assumption to this taxonomy is that multiple recruitment steps and their corresponding strategies are employed at any given time. From Table 1 and the literature, we formulated the following recruitment goals based on each recruitment step.

Table 1.

Strategies for Recruitment Success for Clinical Research with Bariatric Surgery Patients

Recruitment method	Recruitment strategies
1. Publicity and advertisement	• Appealing posters and fliers in clinic exam rooms, waiting rooms, and other locations visible to potential participants^17–19,22
	• A personalized letter that introduces the study and includes physician endorsement^17–19,22
	• Word of mouth referral by current or former research participants^19,20,29
2. Direct one-on-one contact with potential participants	• Charts stuffed with research flier to prompt clinician to invite eligible patients to participate^29,30
	• Individual communication in the clinical setting^15,25
	• Emphasis on positive aspects of involvement including benefit to others through participation^31,32
	• Discussion of past research results that have benefited society and contributed to healthcare²¹
	• Pointing out potential participant's value as expert in their situation²³
3. Informed consent process	• An interesting and non-threatening study title²²
	• Clear, direct, and simply stated consent form^16,22
	• Thorough verbal explanation to ensure comprehension^16,22
4. Recruiter development	• Participation by recruiters in data collection protocol themselves¹⁶
	• Potential participants greeted with a friendly smile, questions answered with confidence, and risks and shortcomings of the study fully disclosed³³
	• Personal, frequent contact between recruiter and potential participants^15,22,31
	• Easy to reach; phone calls returned promptly²⁰
	• Delay between first identification of interest in study and recruitment and enrollment minimized²⁰
	• Sincere interest in contributing to the health and well-being of those being studied conveyed²¹
	• Recruiter affected by health condition under study if possible¹⁸
5. Clinician and clinic staff involvement	• Clinician endorsement obtained to convey legitimacy and importance of research study¹⁸
	• Desk clerks, nurses, physicians, and other clinicians involved in recruitment activities^29,30
	• A designated staff liaison enlisted to help with recruitment^29,30
	• Recruiter visible and readily available to clinic staff¹⁹
	• Commonalities between research team and clinic staff built upon (e.g., nurse researchers working with clinic nurses)²⁶
6. Cultural sensitivity³¹	• Culturally tailored fliers and posters^16,17,34
	• Matching of ethnicity of recruitment staff with potential participants when possible^16,17,34
	• Acknowledgement of the existence of past problems; discuss in an open and honest way²¹

1. Publicity and advertisement of the study reaches all potential participants and stimulates interest in participation.²³

2. Direct one-on-one recruitment fosters interest, optimism, and confidence about participation.

3. Potential participants fully understand the data collection protocol by way of the informed consent process.

4. Recruiters gain the trust of potential participants through their professionalism and the building of nurturing relationships.¹⁵

5. Collaborative and collegial relationships and a team spirit are developed between recruiters and clinicians/clinic staff.²³

6. Cultural sensitivity facilitates feelings of welcome and respect for potential participants of diverse backgrounds and allows recruitment of a diverse study sample.

Methods and Materials

Mindful of the recruitment barriers most expected because of the nature of the pilot study and working within the blueprint of successful recruitment strategies listed in Table 1, we developed a recruitment plan. Before writing the IRB application, the principal investigator met with the director of the bariatric surgery program and her staff to plan the best approach for recruiting participants for the study. The IRB requested that recruitment take place in multiple phases and be separate from the baseline data collection so that potential participants had time to make their decision about whether to participate. Based on the processes required before bariatric surgery, the principal investigator developed a three-phase recruitment plan. The first phase encompassed publicity and advertisement and incorporated the recruitment strategies listed under Recruitment Step #1 in Table 1. To convey clearly the type of participant needed, the fliers and posters invited research participation based upon the following inclusion criteria: female, age 19 years or older, upcoming primary bariatric surgery, and history of childhood abuse. The clinic staff was provided an ample supply of fliers, as well as an electronic copy to make more copies if needed.

The second recruitment phase involved direct one-on-one contact with potential participants (Recruitment Step #2 in Table 1). The graduate assistant (GA) hired for the study was the primary recruiter, with the principal investigator serving as a back-up recruiter. The IRB-approved recruitment plan specified that direct one-on-one contact with potential participants should take place during the first bariatric surgery clinic visit. After showing patients the flier, clinicians asked potential participants if they had considered participating in the study. Potential participants were assured that participation was purely voluntary and would not affect their care before or after surgery. If a potential participant expressed interest, the clinician invited the recruiter into the exam room to provide more information about the study. If the response was affirmative, the recruiter entered the room and in private asked the following screening question: “In order to be eligible for the study, you have to have been a victim of childhood sexual abuse before the age of 18. Does that apply in your case?” If the potential participant replied “yes,” the recruiter asked her if she was interested in participating in the study, and used the recruitment strategies as delineated in Recruitment Step #2.

Using the recruitment strategies of Recruitment Step #3 in Table 1, informed consent was obtained for patients who agreed to be in the study. The title of the study was “Factors Related to Bariatric Surgery Outcomes: A Pilot Study.” Multiple drafts of the informed consent were written, with many individuals reading each draft until a satisfactory version that accurately described the study protocol was agreed upon and subsequently approved by the IRB. Once consented, participants did not begin their first round of data collection (the presurgery baseline data) until the day of their preoperative history and physical visit, generally scheduled within 2 weeks of surgery.

The remaining recruitment steps listed in Table 1 were incorporated throughout the recruitment process. For recruiter development (Recruitment Step # 4 in Table 1), the GA was an experienced registered nurse working on a master's degree to become an advanced practice nurse. She brought to the recruiter position experience in working with endocrine protocols at a reproductive health clinic. The GA provided verbal and written explanations of the study in an unhurried fashion, allowing plenty of time to have potential participants' questions answered and concerns addressed. Participants were given office and cell phone numbers and e-mail addresses of the principal investigator and GA for any future questions. Although the GA had never experienced bariatric surgery herself, she demonstrated compassion for the dual stigmas of obesity and CSA, and the difficulty of making the decision to have surgery.

Clinic staff involvement (Recruitment Step #5 in Table 1) was initiated and fostered by the director of the bariatric surgery program, who called a clinic staff meeting to introduce the principal investigator and discuss the study. The GA kept in close contact with clinic staff and the clinic liaison by telephone, e-mail, or text messages for appointment schedules and potential participants. Clinicians and clinic staff members were invited for coffee with the recruiters periodically to discuss recruitment strategies and progress, invite ideas and suggestions, problem solve, and give appreciation and encouragement. In order to show respect and appreciation to the clinicians and clinic staff for all their efforts and to maintain a collaborative team spirit, gift cards and edible treats were given as a tangible “thank you.”

To foster cultural sensitivity (Recruitment Step #6 in Table 1), pictures on the posters and fliers were of ethnically diverse individuals before and after bariatric surgery. While the GA was not a minority member, she had lived among and worked with diverse populations during her previous career as a military nurse. Finally, participation in the study was made as convenient as possible. Data collection and provisions of materials for saliva collection coincided with three regularly scheduled clinic visits. Participants were offered convenient locations for return delivery of the saliva specimens the following week, including pick-ups in their neighborhood and a drive-by option in front of the academic health center. Out-of-town participants were provided pre-paid mailers.

Results

The first problem with recruitment was revealed early in the process. Within 6 weeks of beginning the study, 23 female patients came to the clinic for their first bariatric surgery visit, but none were recruited. Only two of these patients allowed a recruiter into the exam room, but then denied experiencing any childhood abuse. (They admitted to not reading the flier.) Another two patients contacted the recruiter directly and answered affirmatively to the CSA screening question but chose not to participate in the pilot study. The research team suspected that the sensitive nature of childhood abuse and the stigma of CSA were proving to be a greater recruitment barrier than anticipated. Eligible patients may not have wanted to admit past childhood abuse of any kind to their clinician, even indirectly by stating they would talk to a recruiter. The two eligible patients who decided not to participate in the study may have decided that having bariatric surgery and simultaneously participating in a study with an apparent focus on CSA would be too stressful.

Because collecting longitudinal data was necessary for the pilot study, the recruitment problem had to be addressed quickly. It was decided to open the study to all bariatric surgery patients, including males, regardless of their CSA history. We believed the scientific and feasibility merits of the pilot study would not be compromised because we would still be measuring self-reported CSA and other forms of childhood abuse, but through a less detailed questionnaire suitable for both genders. Helpful advice was also received from a clinic staff member who had undergone bariatric surgery herself and understood the many requirements for surgery. She suggested that the fliers and posters clearly state that participation in the study would not affect eligibility for bariatric surgery.

In addition, a change was made in recruitment practices. The GA started attending the bariatric surgery clinic. Previously, she had waited in her office in another building on call, as suggested originally by the clinic staff. Given the limited clinic space, the principal investigator and GA wanted to honor the clinic staff's wishes. However, this arrangement impeded the visibility of the GA. The GA started sitting in the waiting room so that she was readily available if a patient expressed interest in the study. Further, sitting visibly in the waiting room in a white laboratory coat with the academic health center's insignia made her a constant reminder of the study to the clinic staff.

Three months after study recruitment was initiated, the first participant was enrolled under the revised protocol. Within the next 3 months, a total of nine participants were enrolled. This was far better progress than the first 3 months, but still only half the number of participants needed. Further, considering the total number of bariatric surgery patients (73) who had their first bariatric surgery clinic visit during the second 3 months, the rate of recruitment was poor (12%).

Compounding our recruitment difficulties was a major problem that became evident only after we had been recruiting for 6 months. After 6 months, only one of the nine recruited participants had undergone her presurgery baseline round of data collection. It was becoming apparent that after the first bariatric surgery consultation visit, most patients had to wait at least 6 months for approval by insurers, with some longer. This unforeseen lengthy insurance approval process delayed the initiation of data collection.

Once again, we revised our recruitment plan. With IRB approval, we replaced recruitment at the first bariatric surgery visit with recruitment at the history and physical visit scheduled within 2 weeks of surgery. The bariatric surgeons were performing fewer surgeries than in previous years (down to one or two per week) due to unavoidable internal and external circumstances. Nonetheless, our luck in recruiting greatly improved during this period. Once recruitment at the history and physical visit was initiated, we were able to recruit 12 out of the 25 scheduled patients (50%) over the next 5 months.

As the patients recruited earlier at the first bariatric surgery clinic visit become eligible for surgery, a best guess had to be made on when to stop recruiting more patients, as it was difficult to determine which of these individuals still wanted to complete the study. Seventeen months after starting recruitment, we had 19 participants who had completed at least one round of data collection. Recruitment was stopped one short of the desired sample size in order to complete data collection in a timely manner for publications and a grant application for a fully powered study.

Given our initial optimism and subsequent difficulties with recruitment, the 50% recruitment rate at the history and physical visit was a relief. This satisfactory recruitment rate was no doubt based on a culmination of three contributing circumstances. First, we learned early in the recruitment process that the barrier of double stigma (obesity and CSA) was impossible to overcome in a timely manner. Opening the study to all bariatric surgery patients both reduced the stigma of the study and increased the pool of potential participants. Second, recruitment at the history and physical visit turned out to be the ideal time for recruitment. Patients appeared to be more willing to participate knowing that surgery was approved and imminent. In addition, at the history and physical visit, patients may have been more likely to view their personal goals as a match for the goals of the research (i.e., factors that affect weight loss after bariatric surgery). Finally, we were more experienced with recruiting bariatric surgery patients by the time we started recruiting at the history and physical visit. We were better known to the clinicians and clinic staff, and understood better the clinic processes. Table 2 summarizes the lessons learned, listing the four most unanticipated recruitment challenges encountered while conducting this pilot study with bariatric surgery patients and the corresponding strategies that were developed to surmount these challenges.

Table 2.

Lessons Learned from Recruitment Challenges in Bariatric Surgery Research

Challenges	Strategies
A sensitive or stigmatizing condition as a research topic may reduce recruitment rates.	• Open recruitment to all bariatric surgery patients and measure the sensitive or stigmatizing condition confidentially using a valid and reliable instrument as a part of overall data collection.
	• Emphasize to potential participants that privacy and confidentiality are assured.
	• Obtain informed consent and data collection in a private setting.
Long waits before bariatric surgery is approved is the norm and can delay completion of longitudinal studies.	• Work with Investigational Review Boards (IRBs) to gain approval to use the history and physical visit for direct one-on-one recruitment efforts and for gaining informed consent.
The processes and hurdles involved in achieving approval for bariatric surgery are lengthy and time-consuming.	• Request feedback from clinic staff and other individuals who have experienced bariatric surgery while planning recruitment strategies.
Recruiter non-affiliation with clinic makes remaining visible and available to clinic staff difficult.	• Sit in the waiting room while potential participants are being seen and wear a laboratory coat with institutional and professional insignia.
	• Collaborate with at least one clinic staff liaison who will remind clinicians to ask potential participants if they would be willing to talk to a recruiter.

Our feasibility data on rates of compliance with the study protocol and retention were as encouraging as our final recruitment rate, especially given the complexity and longitudinal characteristics of the data collection protocol. In sum, the saliva samples were returned from 14 participants for all three rounds of data collection. Seventeen participants provided at least some data for their final round of data collection. One participant dropped out before the final round of data collection because of a medical condition, and another dropped out because of a busy schedule. These compliance (74%) and retention (89%) rates were no doubt nurtured by the very same successful strategies that we used for recruitment.

Because of changes made to the initial recruitment plan, we were particularly interested in the proportion of participants who reported past CSA. In our sample, a quarter (n=5; 26%) reported having experienced moderate to severe CSA as measured by the Childhood Trauma Questionnaire.²⁸ These data are similar to previous research findings on bariatric surgery patients.^7,8 Most of the participants in our pilot study were female (n=15; 79%), which mirrors the proportion of females who have bariatric surgery at the academic health center where the study took place. The majority of participants were Caucasian, while three (16%) were African American. According to the academic health center's database, the racial/ethnic profile of bariatric surgical patients over the 2 years prior to the pilot study was 94% Caucasian, 5% African American, and 1% Hispanic.

Conclusion

The lessons learned during the recruitment process for a pilot study about factors that affect bariatric surgery outcomes were shared in this article. Researchers and bariatric surgery nurses can use this information to implement efficient and effective recruitment plans. Because our pilot study addressed a sensitive and stigmatizing topic and had a rigorous data collection protocol, we knew that recruitment would be particularly challenging. Therefore, we designed a recruitment plan that was based on successful strategies documented in the literature to reduce barriers that were particularly pertinent to our pilot study. However, unanticipated barriers were soon encountered and slowed our progress in recruitment. The sensitivity of childhood abuse and the stigma of CSA required us to widen our recruitment efforts to all bariatric surgery patients. Further, the initial IRB request that enrollment and the first round of data collection be separated threatened completion of the pilot study due to the lengthy 6-month approval process required by most insurers. This required an IRB-approved change in the timing of recruitment to the history and physical visit. While a successful move in the end, this unanticipated challenge extended data collection considerably. In addition, we received feedback from clinic staff members who had experienced bariatric surgery improved communication regarding potential participant concerns about participation. Finally, we discovered that being physically present in the waiting room provided availability and visibility for our study and study staff, and also kept us from disrupting busy clinic routines. These changes along with collaborative teamwork among research members, clinicians, and clinic staff allowed us to complete the pilot study and collect the feasibility data we needed for conducting a fully powered study.

Footnotes

Acknowledgments

The authors would like to thank all of the clinicians and clinic staff of the Bariatric Program at the University of Nebraska Medical Center for their invaluable support of this pilot study. In particular, we wish to thank Melissa Monzu-Sparks, RN, BSN, CBN and Linda Neumann-Potash, RN, MSN, CBN.

Disclosure Statement

No competing financial interests exist.

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