Recruitment for controlled clinical trials: literature summary and annotated bibliography

Factors Associated With Enrollment to a Decentralized Study

OBJECTIVE

To assess whether the mode and formatting of invitations affect enrollment in a large, decentralized study.

PATIENTS AND METHODS

Between July 1, 2022, and October 30, 2022, we prospectively compared various approaches to enroll patients in the Tapestry DNA Sequencing Research Study, a decentralized exome-sequencing study. In phase 1, patients were randomized to receive invitations via the electronic health record (EHR) patient portal or email (cohort 1, 69,852 patients). Phase 2 randomized in a 2×2 factorial design to receive (by portal or email) standard or enhanced (ie, more visually appealing) invitations (cohort 2, 26,198 patients). Factors that predicted enrollment rates were analyzed.

RESULTS

The enrollment rate was greater in cohort 2 (1,785 of 24,550, 7.27%) than 1 (1,758 or 69,765, 2.52%) and remained significant after multivariable adjustment (odds ratio, 1.31; 95% CI, 1.19-1.45). Enrollment rates were greater in women than men, patients 50 to 70 years of age than younger patients, White or non-Hispanic or Latino patients than those in other racial categories, urban than rural residents, and patients who had more health care encounters or more recent health care before this study (P<.02). The enrollment rate was also greater when invitations were delivered via EHR than email (odds ratio, 1.56; 95% CI, 1.44-1.68; P<.001).

CONCLUSION

Invitations via EHR rather than email facilitate enrollment to large, decentralized studies. Enhanced display of invitation material did not increase enrollment. Lower enrollment rates in men, younger individuals, non-White and Hispanic individuals, and rural residents highlight a continued need to focus enrollment strategies on these subgroups.

Assessment and ascertainment in psychiatric molecular genetics: challenges and opportunities for cross-disorder research

Psychiatric disorders are highly comorbid, heritable, and genetically correlated [1-4]. The primary objective of cross-disorder psychiatric genetics research is to identify and characterize both the shared genetic factors that contribute to convergent disease etiologies and the unique genetic factors that distinguish between disorders [4, 5]. This information can illuminate the biological mechanisms underlying comorbid presentations of psychopathology, improve nosology and prediction of illness risk and trajectories, and aid the development of more effective and targeted interventions. In this review we discuss how estimates of comorbidity and identification of shared genetic loci between disorders can be influenced by how disorders are measured (phenotypic assessment) and the inclusion or exclusion criteria in individual genetic studies (sample ascertainment). Specifically, the depth of measurement, source of diagnosis, and time frame of disease trajectory have major implications for the clinical validity of the assessed phenotypes. Further, biases introduced in the ascertainment of both cases and controls can inflate or reduce estimates of genetic correlations. The impact of these design choices may have important implications for large meta-analyses of cohorts from diverse populations that use different forms of assessment and inclusion criteria, and subsequent cross-disorder analyses thereof. We review how assessment and ascertainment affect genetic findings in both univariate and multivariate analyses and conclude with recommendations for addressing them in future research.

The role of artificial intelligence in drug screening, drug design, and clinical trials

The role of computational tools in drug discovery and development is becoming increasingly important due to the rapid development of computing power and advancements in computational chemistry and biology, improving research efficiency and reducing the costs and potential risks of preclinical and clinical trials. Machine learning, especially deep learning, a subfield of artificial intelligence (AI), has demonstrated significant advantages in drug discovery and development, including high-throughput and virtual screening, ab initio design of drug molecules, and solving difficult organic syntheses. This review summarizes AI technologies used in drug discovery and development, including their roles in drug screening, design, and solving the challenges of clinical trials. Finally, it discusses the challenges of drug discovery and development based on AI technologies, as well as potential future directions.

Facilitation of Enrollment onto Cancer Clinical Trials Using a Novel Navigator-Assisted Program: A Cross-Sectional Study

INTRODUCTION

Clinical trials are essential to the advancement of clinical therapies that improve the outcomes of people with cancer. However, enrollment in clinical trials remains a challenge. The Clinical Trial Navigator [CTN] Program was designed to address the current gap in the cancer care journey by assisting with the clinical trials search process.

METHODS

Between March 2019 and July 2024, applicants of the CTN program included people with cancer, their family members, and/or their care team. Applicants entered the CTN program through a REDCap® survey that collected the patient's medical history. A final curated list of potential clinical trials was provided to the applicant. Metrics of success included clinical trial referral and enrollment, and we examined the factors that impacted these outcomes.

RESULTS

A total of 445 people with cancer applied to the CTN program during the study. Of the 262 patients with referral and enrollment information, a trial referral occurred in 27.5% [n = 72]. Of the 72 patients who were referred to a clinical trial, 13 [18.1%] were enrolled, 9 [12.5%] are pending enrollment, and 50 [69.4%] were not enrolled. We identified a potential trial for 88% of applicants, with a median of one potential trial per patient. Physicians were highly involved as applicants.

INTERPRETATION

The CTN program is successful in searching for clinical trials for people with cancer. Ongoing implementation into other Canadian sites, assessments of patient-reported outcomes, website and social media campaigns, and research into the factors that impact referral and enrollment are underway.

Successes and Challenges in Clinical Trial Recruitment: The Experience of a New Study Team

Participant recruitment is one of the most challenging aspects of a clinical trial, directly impacting both the study's duration and the quality of its results. Therefore, reporting successful recruitment strategies is crucial. This study aimed to document the recruitment tactics and experiences of a research team during a university-based randomized clinical trial, conducted as part of a clinical research immersion program. Recruitment took place from October 2021 to October 2022. Before the study commenced, study team members received formal training in clinical trial participant recruitment from the Principal Investigator. The recruitment strategies were integrated into initial study design, which was approved by the Institutional Review Board. A multimodal approach was employed, incorporating both direct and indirect recruitment methods. These strategies successfully met the enrollment target within the twelve-month period. Throughout the process, team members acquired valuable knowledge in recruitment design and implementation, along with transferable interpersonal and networking skills. In-person recruitment was the most efficient and cost-effective strategy, followed by personal referrals. The primary challenge was accommodating participants' availability. Other study teams should consider these recruitment strategies during their study designs. Additionally, the knowledge and skills gained by this study team underscore the value of experiential learning in research education.

Social marketing and the challenges of participant recruitment

Recruitment of research participants often has not obtained a desired sample size, thereby becoming a major problem inhibiting investigators' ability to adequately test the specified hypotheses. Social marketing with its four Ps, originally developed by the business world to sell products and adapted for public health initiatives, is proposed as a dynamic comprehensive conceptual framework to apply marketing principles and practices to enhance participant recruitment. Applying a social marketing approach to research recruitment would require initial investigation to understand the motivations of the target audience in regard to research participation, and continued research throughout the main project to adapt the recruitment efforts as limitations arise. Additional funding would be needed for successful social marketing research recruitment programs to be systematically implemented and evaluated as part of research projects. In this paper, we define social marketing concepts, briefly review the available literature supporting social marketing applied to recruitment for research studies, and consider ethical issues that may arise when using a social marketing approach.

Exploring Differences in Screening and Enrollment Metrics in Orthopaedic Clinical Trials

The success of any clinical trial relies heavily on patient recruitment and retention. The purpose of this study was to review screening and enrollment metrics for orthopaedic clinical trials, comparing different patient populations to determine common challenges to recruitment and differences in rates of enrollment. Screening logs and study trackers were manually reviewed for four clinical trials at a single academic institution and included randomized controlled trials (RCTs) and an observational study. Data extracted from these documents included the number of patients screened, number excluded and reasons for exclusion, number enrolled, number of withdrawn and reason. Of the four trials reviewed, the point-of-care diagnostic test had the highest number of patients excluded and the lowest patient refusal rate. Refusal rates were highest in the venous thromboembolism prophylaxis study and enrollment rates were the lowest in the RCT of drug treatments and the highest rate in the observational study. The success of the trial relies on the ability to recruit patients and factors need to be considered when recruiting participants including sample size requirements and inclusion and exclusion criteria. These data provide some insights into the patient recruitment experience at our institution with different patient populations and study types, highlighting key points to be aware of when planning for an orthopaedic clinical trial.

Changes in patient recruitment parameters and their derivatives under the influence of external factors – population size and density of residence in a certain area

Background. The lack of targeted patient recruitment for clinical trials reaches 90%, which leads to failures of a trial as a whole and insufficient access to the necessary treatment or diagnostic method for patients. To find out the reasons for recruitment failures, many factors are considered, the action of which is difficult to assess due to high variability. In general, various factors are named that reduce patient recruitment, while factors that improve it are much less known.

Objective: to investigate changes in the parameters and indicators of patient recruitment for clinical trials depending on the influence of external factors.

Material and methods. A retrospective analysis of four international multicenter clinical trials of phases II–III was performed by 16 patient recruitment parameters and their 6 derivatives (indicators) – both widely used in the literature and newly proposed. A total of 622 patients from 70 clinical centers located in 59 cities of Russia, Ukraine, and Belarus were included in the study. The methods of descriptive statistics and typing were used. To study the influence of factors, internal and external factors were selected, external factors including population size, area and density of residence were analysed, and changes in parameters and indicators depending on the influence of each factor were examined. The area and population density were studied in inseparable connection with each other.

Results. A simple classification of factors was proposed – external and internal to the clinical center where patients were recruited. The factors classified as external were analyzed depending on the change in the proposed parameters of patient recruitment for clinical trials and their relationships – indicators (derivatives). The final rate of patient recruitment and the final number of patients recruited in the population group of 1–2 million people had statistically significant (p<0.05) higher values (0.57±0.20 and 15.08±5.06, respectively) than in group with up to 1 million people – 0.14±0.05 and 3.75±1.24.

Conclusion. For the first time, an extended panel of parameters and indicators that allow evaluating the influence of various factors on patient recruitment for clinical trials was proposed. The value of the proportion of parameters and indicators that had statistical differences among themselves in the group influenced by the population size factor was more than twice as large as the proportion of similar parameters and indicators in the group influenced by area and population density: 47% and 23%, respectively, which may indicate more strong influence of the first factor.

Optimizing educational methods for the low FODMAP diet in disorders of gut-brain interaction: A feasibility randomized controlled trial

BACKGROUND

A diet low in fermentable oligo-saccharides, di-saccharides, mono-saccharides and polyols (low FODMAP diet) is complex and clinical effectiveness is achieved with dietitian-led education, although dietitian availability in clinical practice varies. This study aimed to assess the feasibility of undertaking a trial to investigate the clinical and cost-effectiveness of different education delivery methods of the low FODMAP diet in patients with disorders of gut-brain interaction (DGBI).

METHODS

In this feasibility randomized controlled trial, patients with DGBI requiring the low FODMAP diet were randomized to receive one of the following education delivery methods: booklet, app, or dietitian. Recruitment and retention rates, acceptability, symptoms, stool output, quality of life, and dietary intake were assessed.

KEY RESULTS

Fifty-one patients were randomized with a recruitment rate of 2.4 patients/month and retention of 48 of 51 (94%). Nobody in the booklet group strongly agreed that this education delivery method enabled them to self-manage symptoms without further support, compared to 7 of 14 (50%) in the dietitian group (p = 0.013). More patients reported adequate relief of symptoms in the dietitian group (12, 80%) compared with the booklet group (7, 39%; p = 0.026), but not when compared to the app group (10, 63%, p > 0.05). There was a greater decrease in the IBS-SSS score in the dietitian group (mean -153, SD 90) compared with the booklet group (mean -90, SD 56; p = 0.043), but not when compared with the app group (mean -120, SD 62; p = 0.595).

CONCLUSIONS & INFERENCES

Booklets were the least acceptable education delivery methods. Dietitian-led consultations led to high levels of clinical effectiveness, followed by the app, while the dietitian was superior to booklets alone. However, an adequately powered clinical trial is needed to confirm clinical effectiveness of these education delivery methods.

Artificial Intelligence for Personalized Genetics and New Drug Development: Benefits and Cautions

As the global health care system grapples with steadily rising costs, increasing numbers of admissions, and the chronic defection of doctors and nurses from the profession, appropriate measures need to be put in place to reverse this course before it is too late [...].

Clinical Characterization of Inpatients with Acute Conjunctivitis: A Retrospective Analysis by Natural Language Processing and Machine Learning

Background Acute bacterial conjunctivitis (ABC) is a relatively common medical condition caused by different pathogens. Although it rarely threatens vision, it is one of the most common conditions that cause red eyes and may be accompanied by discomfort and discharge. The study aimed to identify and characterize inpatients with ABC treated with topical antibiotics. Methods The EHRead® technology, based on natural language processing (NLP) and machine learning, was used to extract and analyze the clinical information in the electronic health records (EHRs) of antibiotic-treated patients with conjunctivitis and admitted to five hospitals in Spain between January 2014 and December 2018. Categorical variables were described by frequency, whereas numerical variables included the mean, standard deviation, median, and quartiles. Results From a source population of 2,071,812 adult patients who attended the participating hospitals in the study period, 11,110 patients diagnosed with acute conjunctivitis were identified. Six thousand five hundred eighty-three patients were treated with antibiotics, comprising the final study population. Microbiology was tested only on 12.1% of patients. Antibiotics, mainly tobramycin, and corticosteroids, mainly dexamethasone, were usually prescribed. NSAIDs were also used in about 50% of patients, always combined with antibiotics. Conclusions The present study provided a realistic representation of the hospital practice concerning managing patients with acute antibiotic-treated conjunctivitis. The diagnosis is usually based on the clinical ground, microbiology is rarely tested, few bacteria species are involved, and local antibiotics are frequently associated with corticosteroids and/or NSAIDs. Moreover, this study provided clinically relevant outcomes, based on new technology, that could be applied in clinical practice.

Privacy-by-Design Environments for Large-Scale Health Research and Federated Learning from Data

This article offers a brief overview of 'privacy-by-design (or data-protection-by-design) research environments', namely Trusted Research Environments (TREs, most commonly used in the United Kingdom) and Personal Health Trains (PHTs, most commonly used in mainland Europe). These secure environments are designed to enable the safe analysis of multiple, linked (and often big) data sources, including sensitive personal data and data owned by, and distributed across, different institutions. They take data protection and privacy requirements into account from the very start (conception phase, during system design) rather than as an afterthought or 'patch' implemented at a later stage on top of an existing environment. TREs and PHTs are becoming increasingly important for conducting large-scale privacy-preserving health research and for enabling federated learning and discoveries from big healthcare datasets. The paper also presents select examples of successful TRE and PHT implementations and of large-scale studies that used them.

Detecting motor symptom fluctuations in Parkinson's disease with generative adversarial networks

Parkinson's disease is a neurodegenerative disorder characterized by several motor symptoms that develop gradually: tremor, bradykinesia, limb rigidity, and gait and balance problems. While there is no cure, levodopa therapy has been shown to mitigate symptoms. A patient on levodopa experiences cycles in the severity of their symptoms, characterized by an ON state-when the drug is active-and an OFF state-when symptoms worsen as the drug wears off. The longitudinal progression of the disease is monitored using episodic assessments performed by trained physicians in the clinic, such as the Unified Parkinson's Disease Rating Scale (UPDRS). Lately, there has been an effort in the field to develop continuous, objective measures of motor symptoms based on wearable sensors and other remote monitoring devices. In this work, we present an effort towards such a solution that uses a single wearable inertial sensor to automatically assess the postural instability and gait disorder (PIGD) of a Parkinson's disease patient. Sensor data was collected from two independent studies of subjects performing the UPDRS test and then used to train and validate a convolutional neural network model. Given the typical limited size of such studies we also employed the use of generative adversarial networks to improve the performance of deep-learning models that usually require larger amounts of data for training. We show that for a 2-min walk test, our method's predicted PIGD scores can be used to identify a patient's ON/OFF states better than a physician evaluated on the same criteria. This result paves the way for more reliable, continuous tracking of Parkinson's disease symptoms.

Community engagement in kidney research: Guatemalan experience

Background

Community engagement is essential for effective research when addressing issues important to both the community and researchers. Despite its effectiveness, there is limited published evidence concerning the evaluation of community engagement in research projects, especially in the area of nephrology.

Methods

We developed a community engagement program in Guatemala to address the role of hydration in chronic kidney disease of unknown origin, using five key engagement principles: 1. Local relevance and determinants of health. 2. Acknowledgment of the community. 3. Dissemination of findings and knowledge gained to all partners. 4. Usage of community partners’ input. 5. Involvement of a cyclical and iterative process in the pursuit of goals. The effectiveness of community engagement was measured by a structured questionnaire on a 5-point likert scale. This measure determined how well and how often the research team adhered to the five engagement principles. We assessed internal consistency for each set of the engagement items through Omega coefficient.

Results

Sixty-two community leaders completed the questionnaire. Seventy-five percent were female, with a mean age of 37 years. All 5 engagement principles scored highly on the 5-point likert scale. Every item set corresponding to an engagement principles evaluation had a Omega coefficient > 0.80, indicating a firm internal consistency for all question groups on both qualitative and quantitative scales.

Conclusion

Engagement of the community in the kidney research provides sustainability of the efforts and facilitates the achievements of the goals. Community leaders and researchers became a team and develop a relationship in which commitment and empowerment facilitated the participation in all aspects of the research process. This initiative could be a useful tool for researchers, especially in low-middle income countries, to start research in a community, achieve objectives in a viable form, and open opportunities to further studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02891-8.

Success rate of acquiring informed consent and barriers to participation in a randomized controlled trial of laparoscopic versus open surgery for non-curative stage IV colon cancer in Japan (JCOG1107)

BACKGROUND

Successful achievement of randomized controlled trials (RCTs) is dependent on the acquisition of informed consent (IC) from patients. The aim of this study was to prospectively calculate the proportion of participation in a surgical RCT and to identify the reasons for failed acquisition of IC.

METHODS

A 50-insitution RCT was conducted to evaluate oncological outcomes of open and laparoscopic surgery for stage IV colon cancer (JCOG1107: UMIN-CTR 000000105). The success rate of obtaining IC was evaluated in eight periods between January 2013 and January 2021. In addition, reasons for failed acquisition of IC were identified from questionnaires.

RESULTS

In total, 391 patients were informed of their eligibility for the trial, and 168 (42%) were randomly assigned to either the laparoscopic surgery group (n = 84) or open surgery group (n = 84). The success rate of IC acquisition ranged from 33 to 58% in three periods. The most common reasons for failed IC acquisition were the patients' preference for one approach of surgery based on recommendations from referring doctors and family members, and anxiety/unhappiness about randomization.

CONCLUSIONS

The success rate of acquiring IC from patients for an RCT of laparoscopic versus open surgery for stage IV colon cancer was lower than the expected rate planned in the protocol. To obtain the planned rate, investigators should make efforts to inform patients and their families about the medical contributions a surgical RCT can make and recognize that the period in equipoise may be limited.

Assessment of Patients' Willingness to Participate in a Randomized Trial of Spinal versus General Anesthesia for Lumbar Spine Surgery

BACKGROUND

Prospective nonrandomized studies have found less postoperative fatigue and improved quality of life in patients undergoing awake spine surgery under spinal anesthesia compared with general anesthesia. Randomized trials are needed to validate these findings.

OBJECTIVE

To prospectively investigate patients' willingness to enroll in randomized trials of lumbar spine surgery under spinal versus general anesthesia and identify any potential barriers.

METHODS

We recruited patients undergoing lumbar spine surgery for degenerative disease. We described a randomized trial of spine surgery under spinal versus general anesthesia and assessed patients' willingness to participate in such trial. We elicited preferences for treatment along with demographics. The association between these factors and willingness to participate in the trial was examined.

RESULTS

Fifty patients completed interviews; 58% were female, mean age of 60.9 ± 12.5 years. A total of 52% patients stated that they were definitely willing to participate in the hypothetical randomized trial, and 8% probably willing. Only 16% of patients were aware of spinal anesthesia as an option for low back surgery, and 60% indicated no strong preference for the anesthesia techniques. Patients without strong preferences stated a greater willingness to participate than those with strong preferences (80% vs. 10% definitely willing, P < 0.0001). Age, sex, education, work status, and race were not significantly associated with willingness to participate.

CONCLUSION

Sixty percent of patients stated that they were either definitely or probably willing to participate in the randomized trial. Subjects lacking strong preferences for the anesthesia technique stated a greater willingness to enroll than those with strong preference.

Factors that influence community hospital involvement in clinical trials: A qualitative descriptive study

RATIONALE, AIMS AND OBJECTIVES

The successful conduct of randomized clinical trials (RCTs) is often impeded by recruitment difficulties. Community hospitals see large volumes of patients but rarely participate in trials. The objective of this study was to explore how research stakeholders identify and understand the contextual, organizational, research, and individual-level factors that influence the engagement of community hospitals in Ontario to participate in RCTs as partner sites.

METHODS

In this descriptive, qualitative study, semi-structured interviews were conducted with a purposeful sample of 18 individuals who are familiar with the processes associated with engaging community hospitals for research or recruiting participants from these sites into trials. Demographic data were summarized using descriptive statistics. The principles of conventional content analysis were used to code, categorize and synthesize the interview data.

RESULTS

Informed by participants' descriptions, the results were organized within three unique stages that describe the process of recruitment within community hospitals: (a) community hospital engagement; (b) initiation of the project in the community hospitals; and (c) recruiting patients. The key barriers were the invisibility of the community hospitals to research investigators and the lack of research infrastructure in most of the community hospitals. Increased communication and sharing of resources between academic centers and community hospitals facilitated recruitment across all three stages.

CONCLUSION

Our results illustrated a willingness of community hospitals to participate in RCTs, but a lack of capacity for research. Additional efforts by trial coordinating sites are required to recruit community hospitals, but their inclusion improves the generalizability of trial results.

The Recruitment Innovation Center: Developing novel, person-centered strategies for clinical trial recruitment and retention

Clinical trials continue to face significant challenges in participant recruitment and retention. The Recruitment Innovation Center (RIC), part of the Trial Innovation Network (TIN), has been funded by the National Center for Advancing Translational Sciences of the National Institutes of Health to develop innovative strategies and technologies to enhance participant engagement in all stages of multicenter clinical trials. In collaboration with investigator teams and liaisons at Clinical and Translational Science Award institutions, the RIC is charged with the mission to design, field-test, and refine novel resources in the context of individual clinical trials. These innovations are disseminated via newsletters, publications, a virtual toolbox on the TIN website, and RIC-hosted collaboration webinars. The RIC has designed, implemented, and promised customized recruitment support for 173 studies across many diverse disease areas. This support has incorporated site feasibility assessments, community input sessions, recruitment materials recommendations, social media campaigns, and an array of study-specific suggestions. The RIC’s goal is to evaluate the efficacy of these resources and provide access to all investigating teams, so that more trials can be completed on time, within budget, with diverse participation, and with enough accrual to power statistical analyses and make substantive contributions to the advancement of healthcare.

Costing a population health management approach for participant recruitment to a diabetes prevention study

Limited research has reported the economic feasibility-from both a research and practice perspective-of efforts to recruit and enroll an intended audience in evidence-based approaches for disease prevention. We aimed to retrospectively assess and estimate the costs of a population health management (PHM) approach to identify, engage, and enroll patients in a Type 1 Hybrid Effectiveness-Implementation (HEI), diabetes-prevention trial. We used activity-based costing to estimate the recruitment costs of a PHM approach integrated within an HEI trial. We took the perspective of a healthcare system that may adopt, and possibly sustain, the strategy in the typical practice. We also estimated replication costs based on how the strategy could be applied in healthcare systems interested in referring patients to a local diabetes prevention program from a payer perspective. The total recruitment and enrollment costs were $360,424 to accrue 599 participants over approximately 15 months. The average cost per screened and enrolled participant was $263 and $620, respectively. Translating to the typical settings, total recruitment costs for replication were estimated as $193,971 (range: $43,827-$210,721). Sensitivity and scenario analysis results indicated replication costs would be approximately $283-$444 per patient enrolled if glucose testing was necessary, based on the Medicare-covered services. From a private payer perspective, and without glucose testing, per-participant assessed costs were estimated at $31. A PHM approach can be used to accrue a large number of participants in a short period of time for an HEI trial, at a comparable cost per participant.

Barriers and facilitators to the participation of subjects in clinical trials: An overview of reviews

BACKGROUND

The demand for clinical trial participants is today one of the highest it has ever been and continues to increase. At the same time, subject recruitment continues to be problematic and the major reason for clinical trial premature terminations. The literature on clinical trial recruitment, which spans several decades and includes hundreds of studies, has an abundance of findings that can be synthesized by way of an overview to provide a well-informed and complete picture of the factors that determine subject participation.

OBJECTIVES

An overview of the systematic reviews that report barriers and facilitators to clinical trial participation was conducted. The extracted data were synthesized, and a thematic framework of the factors that affect subject participation in clinical trials was developed. The overview extended across medical subjects and demographics.

METHODS

Thirty reviews that complied with the inclusion criteria were included. These reviews covered 753 relevant primary studies and reported 881 barriers and facilitators. The barriers and facilitators were thematically synthesized and a thematic framework of 20 themes was developed. The quality of the included reviews was assessed and reported.

MAIN RESULTS

Several opportunities to increase clinical trial participation, by developing interventions and changing the trial design, derived from an analysis of the thematic framework. That analysis also showed that most of the 20 themes operate mainly as a barrier or as a facilitator, and that most have an effect across medical subjects. As to the quality elements assessed, some reviews complied almost fully but most only partially.

Building a specialized lexicon for breast cancer clinical trial subject eligibility analysis

A natural language processing (NLP) application requires sophisticated lexical resources to support its processing goals. Different solutions, such as dictionary lookup and MetaMap, have been proposed in the healthcare informatics literature to identify disease terms with more than one word (multi-gram disease named entities). Although a lot of work has been done in the identification of protein- and gene-named entities in the biomedical field, not much research has been done on the recognition and resolution of terminologies in the clinical trial subject eligibility analysis. In this study, we develop a specialized lexicon for improving NLP and text mining analysis in the breast cancer domain, and evaluate it by comparing it with the Systematized Nomenclature of Medicine Clinical Terms (SNOMED CT). We use a hybrid methodology, which combines the knowledge of domain experts, terms from multiple online dictionaries, and the mining of text from sample clinical trials. Use of our methodology introduces 4243 unique lexicon items, which increase bigram entity match by 38.6% and trigram entity match by 41%. Our lexicon, which adds a significant number of new terms, is very useful for matching patients to clinical trials automatically based on eligibility matching. Beyond clinical trial matching, the specialized lexicon developed in this study could serve as a foundation for future healthcare text mining applications.

A comparison of two mail-based strategies to recruit older cancer survivors into a randomized controlled trial of a lifestyle intervention

Purpose

To compare response rates to business letter versus greeting card invitations used to recruit older cancer survivors to a randomized controlled clinical trial of a lifestyle intervention

Methods

Capitalizing upon recruitment efforts for a lifestyle intervention trial among older cancer survivors, we explored response rates to study invitations formatted as greeting cards versus standard business letters. Survivors were identified from cancer registries and medical records and randomly assigned with strata defined by gender and racial/ethnicity to one-of-the-two invitations. Both groups received telephone follow-up.

Results

Contact was verified among 708 survivors with an average age of 72 years with most being non-Hispanic White (NHW), urban dwelling, and female. Survivors assigned to the business letter (n = 360) as compared to the greeting card (n = 348) were significantly more likely to express interest in participation (OR 1.73, 95% CI 1.11–2.70). With the exception of racial/ethnic minorities (OR 0.73; 95% CI 0.26–2.11), all other subgroups favored the business letter with significance observed in females (OR 1.66, 95% CI 1.00–2.74), NHWs (OR 2.12; 95% CI 1.29–3.49), and rural dwellers (OR 3.61; 95% CI 1.49–8.76). Moreover, the business letter costs were substantially lower than the card.

Conclusion

Clinical trial recruitment is significantly more effective if solicitations are formatted as standard business letters as compared to greeting cards, though this may not generalize to racial/ethnic minorities where more research is warranted.

Implications for Cancer Survivors

These study findings are not only valuable to researchers but also have the potential to improve recruitment and engagement of older cancer survivors in clinical trials.

Clinical Trial Registration

Harvest for Health for in Older Cancer Survivors, ClinicalTrials.gov Identifier: NCT02985411

Centralized registry for COVID-19 research recruitment: Design, development, implementation, and preliminary results

BACKGROUND

The Coronavirus Disease 2019 (COVID-19) pandemic has had substantial global morbidity and mortality. Clinical research related to prevention, diagnosis, and treatment of COVID-19 is a top priority. Effective and efficient recruitment is challenging even without added constraints of a global pandemic. Recruitment registries offer a potential solution to slow or difficult recruitment.

OBJECTIVES

The purpose of this paper is to describe the design and implementation of a digital research recruitment registry to optimize awareness and participant enrollment for COVID-19-related research in Baltimore and to report preliminary results.

METHODS

Planning began in March 2020, and the registry launched in July 2020. The primary recruitment mechanisms include electronic medical record data, postcards distributed at testing sites, and digital advertising campaigns. Following consent in a Research Electronic Data Capture survey, participants answer questions related to COVID-19 exposure, testing, and willingness to participate in research. Branching logic presents participants with studies they might be eligible for.

RESULTS

As of March 24, 2021, 9010 participants have enrolled, and 64.2% are female, 80.6% are White, 9.4% are Black or African American, and 6% are Hispanic or Latino. Phone outreach has had the highest response rate (13.1%), followed by email (11.9%), text (11.4%), and patient portal message (9.4%). Eleven study teams have utilized the registry, and 4596 matches have been made between study teams and interested volunteers.

CONCLUSION

Effective and efficient recruitment strategies are more important now than ever due to the time-limited nature of COVID-19 research. Pilot efforts have been successful in connecting interested participants with recruiting study teams.

A knowledge base of clinical trial eligibility criteria

OBJECTIVE

We present the Clinical Trial Knowledge Base, a regularly updated knowledge base of discrete clinical trial eligibility criteria equipped with a web-based user interface for querying and aggregate analysis of common eligibility criteria.

MATERIALS AND METHODS

We used a natural language processing (NLP) tool named Criteria2Query (Yuan et al., 2019) to transform free text clinical trial eligibility criteria from ClinicalTrials.gov into discrete criteria concepts and attributes encoded using the widely adopted Observational Medical Outcomes Partnership (OMOP) Common Data Model (CDM) and stored in a relational SQL database. A web application accessible via RESTful APIs was implemented to enable queries and visual aggregate analyses. We demonstrate CTKB's potential role in EHR phenotype knowledge engineering using ten validated phenotyping algorithms.

RESULTS

At the time of writing, CTKB contained 87,504 distinctive OMOP CDM standard concepts, including Condition (47.82%), Drug (23.01%), Procedure (13.73%), Measurement (24.70%) and Observation (5.28%), with 34.78% for inclusion criteria and 65.22% for exclusion criteria, extracted from 352,110 clinical trials. The average hit rate of criteria concepts in eMERGE phenotype algorithms is 77.56%.

CONCLUSION

CTKB is a novel comprehensive knowledge base of discrete eligibility criteria concepts with the potential to enable knowledge engineering for clinical trial cohort definition, clinical trial population representativeness assessment, electronical phenotyping, and data gap analyses for using electronic health records to support clinical trial recruitment.

Examining recruitment feasibility and related outcomes in adults post-stroke

Background

There are limited effective and evidence-based interventions for upper extremity hemiparesis post-stroke. To prepare for an RCT and minimize misuse of resources, there is value in conducting a feasibility study.

Objective

To examine the feasibility of recruitment and other related outcomes for an intense upper limb intervention.

Methodology

Feasibility outcomes included retention, adherence, accrual rate, sample characteristics, and identification of productive recruitment methods. Other outcomes included satisfaction with the study, fidelity, and equipoise of both staff and participants.

Results

Participants were enrolled at a rate of 1.33 per month. The recruitment timeline had to be extended by 4 months, to meet the target of 16 randomized participants. Staggered recruitment was the most successful strategy. We found that following up with individuals who missed initial appointments prior to study enrollment led to decreased adherence.

Conclusion

It is feasible to recruit and retain post-stroke participants for an intense intervention study.

Trial registration

NCT02277028

Does a video clip enhance recruitment into a parenting trial? Learnings from a study within a trial

Background

Reaching recruitment targets in randomised controlled trials is a challenge. Media tools are increasingly used to engage participants, yet there is a paucity of research into the use of video to optimise recruitment. We therefore tested whether adding a participant information video clip to a standard participant information sheet improved recruitment into a parenting trial.

Methods

One hundred seven participants were randomised to receive either a participant information sheet (n = 51) or an informational video clip (n = 56) as part of an email contact following a screening phase. All participants went on to receive the information sheet as part of the existing consent procedure.

Results

The video condition did not increase the odds of recruitment into the trial, such that those in the video condition were significantly less likely to participate in the main trial (OR = 0.253, CI = 0.104–0.618, p = 0.003).

Conclusion

The introduction of a video clip into the recruitment stages of a parenting trial did not lead to an improvement in recruitment; however, the small sample size precludes definitive inferences. We offer reflections on challenges encountered in implementing the SWAT and suggestions for other researchers seeking to embed recruitment SWATs into similar trials.

Trial registration

Current controlled trials ISRCTN 58327365. Registered on 19 March 2015.

SWAT registration

SWAT 106; Effects of a video clip on recruitment into a randomised trial. Registered on 20 December 2016.

A survey of adult preferences regarding recruitment for pediatric research

OBJECTIVE

Although subject recruitment is one of the most critical aspects of human subject research, there is a lack of studies prospectively examining the recruitment preferences of adults for research involving children.

METHODS

This was a cross-sectional study of adults accompanying patients at an otolaryngology clinic in a pediatric medical center. Anonymous questionnaires were distributed in English and Spanish to one adult for every patient. Questions assessed the respondent's preferences for research recruitment including contact method preferences, contact preferences for medical profession type, and whether they would expect a child to receive a small gift for participating in a research study. Fisher's exact tests were used to assess the association between the primary predictor, language, and each outcome.

RESULTS

566 surveys were collected. 505 (89.1%) were completed in English and 61 (10.7%) were completed in Spanish. Spanish-speaking respondents were more likely to prefer talking to a doctor (76.7%) than English-speaking respondents (40.1%, p < 0.05). Spanish-speaking respondents were more likely to prefer talking over the phone (48.3%) than English-speaking respondents (17.3%, p < 0.05). Spanish-speaking respondents were more likely to prefer communicating via text messaging (41.7%) than English-speaking respondents (16.3%, p < 0.05). English-speaking respondents were more likely to prefer communicating through the patient portal of an electronic health record (EHR) (19%) than Spanish-speaking respondents(3.3%, p < 0.05). Mothers were more likely to prefer talking to a nurse/physician's assistant (20%) than fathers (10%, p < 0.05). Mothers were more likely to prefer talking to research staff (20%) than fathers (9%, p < 0.05). Mothers were more likely to prefer communication via text-message (22%) than fathers (6%, p < 0.05). Spanish-speaking respondents were more likely to prefer pediatric patients receiving a small monetary gift for participating in clinical research (70%) than English-speaking respondents (30%, p < 0.05).

CONCLUSION

There was a significant association between preference for recruitment method and primary language spoken by the respondent. Further inquiry is required to understand these differences between English and Spanish speakers.

Recruitment and enrollment of African Americans into health promoting programs: the effects of health promoting programs on cardiovascular disease risk study

Objectives: Randomized controlled trials (RCT) often employ multiple recruitment methods to attract participants, however, special care must be taken to be inclusive of under-represented populations. We examine how recruiting from an existing observational study affected the recruitment of African Americans into a RCT that included yoga-based interventions. In particular, we report the recruitment success of The Effects of Health Promoting Programs (HPP) on Cardiovascular Disease Risk (NCT02019953), the first yoga-based clinical trial to focus only on African Americans. Design: To recruit participants, a multifaceted recruitment strategy was implemented exclusively in the Jackson Heart Study (JHS) cohort. The HPP recruited from the JHS cohort using direct mailings, signs and flyers placed around JHS study facilities, and through JHS annual follow-up interviews. Results: Enrollment into HPP was open to all active JHS participants that were eligible to return for the third clinic exam (n = 4644). The target sample size was 375 JHS participants over a 24 month recruitment and enrollment period. From the active members of the JHS cohort, 503 were pre-screened for eligibility in HPP. More than 90% of those pre-screened were provisionally eligible for the study. The enrollment goal of 375 was completed after a 16-month enrollment period with over 25% (n = 97) of the required sample size enrolling during the second month of recruitment. Conclusions: The findings show that participants in observational studies can be successfully recruited into RCT. Observational studies provide researchers with a well-defined population that may be of interest when designing clinical trials. This is particularly useful in the recruitment of a high-risk, traditionally underrepresented populations for non-pharmacological clinical trials where traditional recruitment methods may prolong enrollment periods and extend study budgets.

Efficiency and Cost: E-Recruitment Is a Promising Method in Gynecological Trials

BACKGROUND

Recruitment of participants is crucial to the success of any trial as it can have a major impact on study costs, the duration of the study itself, and, more critically, trial failure. Given that vulvodynia particularly affects young women, the use of social media and e-recruitment could prove efficient for enrollment.

AIM

To compare the efficiency, effectiveness, and cost-effectiveness of three different recruitment methods.

METHODS

The comparison data were collected as part of a bicentric randomized controlled trial evaluating the efficacy of physiotherapy in comparison with topical lidocaine in 212 women suffering from provoked vestibulodynia. The recruitment methods included: (i) conventional methods (eg, posters, leaflets, business cards, newspaper ads); (ii) health professional referrals, and (iii) e-recruitment (eg, Facebook ads and web initiatives). Women interested in participating were screened by telephone for eligibility criteria and were assessed by a gynecologist to confirm their diagnosis. Once included, structured interviews were undertaken to describe their baseline characteristics.

MAIN OUTCOME MEASURES

The outcomes of this study were the recruitment efficiency (the number of patients screened/enrolled), recruitment effectiveness (the number of participants enrolled), cost-effectiveness (cost per enrolled participant), and retention rate, and baseline characteristics of participants were monitored for each method.

RESULTS

The conventional methods (n = 101, 48%) were more effective as they allowed for greater enrollment of participants, followed by e-recruitment (n = 60, 28%) and health professional referrals (n = 33, 16%) (P < 0.007). Recruitment efficiency was found to be similar for e-recruitment and referrals (60/122 and 33/67, 49%, P = 0.055) but lower for conventional methods (101/314, 32%, P < 0.011). Nonsignificant differences were found between the three groups for baseline characteristics (P ≥ 0.189) and retention rate (91%, P ≥ 0.588). The average cost per enrolled participant was fairly similar for e-recruitment ($117) and conventional methods ($110) and lower for referrals ($60).

CLINICAL IMPLICATIONS

Our results suggest that having a variety of recruitment methods is beneficial in promoting clinical trial recruitment without affecting participant characteristics and retention rates.

STRENGTH & LIMITATIONS

Although recruitment methods were used concomitantly, this study gives an excellent insight into the advantages and limitations of recruitment methods owing to a large sample size.

CONCLUSION

The study findings revealed that e-recruitment is a valuable recruitment method because of its comparable efficiency and cost-effectiveness to health professional referrals and conventional methods, respectively.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, number NCT01455350. Benoit-Piau J, Dumoulin C, Carroll MS, et al. Efficiency and Cost: E-Recruitment Is a Promising Method in Gynecological Trials. J Sex Med 2020;17:1304-1311.

Challenges and practical recommendations for successfully recruiting inactive, statin-free older adults to clinical trials

OBJECTIVES

To outline the challenges and provide practical recommendations for recruiting inactive, statin-free older adults to facilitate feasible study designs. Data was obtained from a double-blind randomised-controlled clinical trial investigating the effects of acipimox versus placebo on muscle function and metabolism in older (65-75 years), inactive, statin-free males. The initial recruitment target was 20 volunteers within 12 months (November 2016-November 2017).

RESULTS

Recruitment occurred via the Exeter 10,000 database containing 236 'eligible' males, a Facebook campaign reaching > 8000 ≥ 65 years old males, 400 directly-addressed letters to ≥ 66 year old males, > 1500 flyers distributed within the community, > 40 emails to local community groups, 4 recruitment talks, 2 magazine adverts and 1 radio advert. Widespread recruitment efforts reaching > 120,000 people led to the recruitment of 20 volunteers (18 completed the clinical trial) within a 25-month timeframe, highlighting the challenge of the timely recruitment of inactive, statin-free older adults for clinical trials. We recommend recruitment for future clinical trials should take a multi-pronged approach from the outset, prioritising the use of volunteer databases, Facebook campaigns and delivering recruitment talks.

Characteristics Associated With Participation in a Behavioral Weight Loss Randomized Control Trial in the U.S. Military

INTRODUCTION

Effective recruitment and subsequent enrollment of diverse populations is often a challenge in randomized controlled trials, especially those focused on weight loss. In the civilian literature, individuals identified as racial and ethnic minorities, men, and younger and older adults are poorly represented in weight loss interventions. There are limited weight loss trials within military populations, and to our knowledge, none reported participant characteristics associated with enrollment. There may be unique motives and barriers for active duty personnel for enrollment in weight management trials. Given substantial costs and consequences of overweight and obesity in the U.S. military, identifying predictors and limitations to diverse enrollment can inform future interventions within this population. The study aims to describe the recruitment, screening, and enrollment process of a military weight loss intervention. Demographic and lifestyle characteristics of military personnel lost between screening and randomization are compared to characteristics of personnel randomized in the study and characteristics of the Air Force in general.

MATERIALS AND METHODS

The Fit Blue study, a randomized controlled behavioral weight loss trial for active duty personnel, was approved by the Institutional Review Board of the Wilford Hall Ambulatory Surgical Center in San Antonio, TX, USA and acknowledged by the Institutional Review Board at the University of Tennessee Health Science Center. Logistic regressions compared participant demographics, anthropometric data, and health behaviors between personnel that attended a screening visit but were not randomized and those randomized. Multivariable models were constructed for the likelihood of being randomized using a liberal entry and stay criteria of 0.10 for the p-values in a stepwise variable selection algorithm. Descriptive statistics compared the randomized Fit Blue cohort demographics to those of the U.S. Air Force.

RESULTS

In univariate analyses, older age (p < 0.02), having a college degree or higher (p < 0.007) and higher military rank (p < 0.02) were associated with completing the randomization process. The randomized cohort reported a lower percentage of total daily kilocalories for fat compared to the non-randomized cohort (p = 0.033). The non-randomized cohort reported more total minutes and intensity of physical activity (p = 0.073). In the multivariate model, only those with a college degree or higher were 3.2 times more likely to go onto randomization. (OR = 3.2, 95% CI = 2.0, 5.6, p < 0.0001). The Fit Blue study included a higher representation of personnel who identified as African American (19.4% versus 15.0%) and Hispanic/Latino (22.7% versus 14.3%) compared with the U.S. Air Force in general; however, men were underrepresented (49.4% versus 80.0%). TABLE I.Comparisons of Demographic Characteristics of Randomized Fit Blue Cohort to Screened Non-Randomized CohortFit Blue Randomized Participants (N = 248)Non-Randomized Cohort (N = 111)All Screened Participants (N = 359)p-ValueSex N (%)0.73 Male122 (49.2)52 (46.8)174 (48.5) Female126 (50.8)59 (53.2)183 (51.5)Age Mean (±SD) years34 (±7.5)32 (±6.7)33 (±7.3)0.02Race N (%)0.89 African American49 (19.8)22 (19.8)71 (19.8) Caucasian163 (65.7)75 (67.6)238 (66.3) Other36 (14.5)14 (12.2)50 (13.9)Ethnicity N (%)0.59 Hispanic/Latino56 (22.6)28 (25.2)84 (23.4) Non-Hispanic/Latino192 (77.4)83 (74.8)275 (76.6)Education N (%)<0.0001 Less than college degree123 (49.6)82 (73.9)205 (57.1) College degree or greater125 (50.4)29 (26.1)154 (42.9)Marital status N (%)0.83 Single/never married40 (16.1)20 (18)60 (16.7) Married/living as married169 (68.1)72 (64.9)241 (67.1) Separated/divorced39 (15.7)19 (17.1)58 (16.2)Number of additional adults in household N (%)0.82 046 (18.5)22 (19.8)68 (18.9) 1162 (65.3)73 (65.8)235 (65.5) 231 (12.5)14 (12.6)45 (12.5) 3 or more9 (3.6)2 (1.8)11 (3.1)Number of children in household N (%)0.56 091 (36.7)37 (33.3)128 (35.7) 159 (23.8)23 (20.7)82 (22.8) 257 (23)26 (23.4)83 (23.1) 3 or more41 (16.5)25 (22.5)66 (18.4)Years in service mean (± SD)12 (±6.6)11 (±6.1)12 (±6.4)0.20Military gradeaN (%)0.02 E1-E434 (13.7)19 (17.1)53 (14.8) E5-E6105 (42.3)58 (52.3)163 (45.4) E7-E952 (21)21 (18.9)73 (20.3) O1-O317 (6.9)9 (8.1)26 (7.2) O4-O639 (15.7)4 (3.6)43 (12)Branch0.68 Army4 (1.6)1 (0.9)5 (1.4) Air Force234 (94.4)105 (94.6)339 (94.4) Navy8 (3.2)5 (4.5)13 (3.6) Marine Corp2 (0.8)0 (0.0)2 (0.6)BMI (m2/kg) N (%)30.6 (±2.7)30.4 (±2.9)30.6 (±2.8)BMI category N (%)0.76 Overweight115 (46.4)52 (48.1)167 (46.9) Obese133 (53.6)56 (51.9)189 (53.1)aMilitary ranking; Enlisted (E) categories: E1-E4 (enlisted), E5-E6 (non-commissioned officers), E7-E9 (senior non-commissioned officers) and two Officer categories (O): O1-O3 (Company Grade Officer) and O4-O6 (Field Grade Officer); standard deviation (SD).Table II.Comparisons of Anthropometric Characteristics of Randomized Fit Blue Cohort to Screened Non-Randomized CohortFit Blue Randomized Participants (N = 248)Non-Randomized Cohort (N = 111)All Screened Participants (N = 359)p-ValuePhysical activity Total physical activity2525 (±3218)2840 (±2541)2621 (±3028)0.027 (mean (±SD) minutes per week) Total sedentary physical activity5046 (±239)472 (±221)494 (±234)0.35 (mean (±SD) minutes per week) Vigorous physical activity34 (±145)54 (±152)40 (±147)0.036 (mean (±SD) minutes per week)Dietary intake Total sweetened beverages (kcal per day)165 (±206)152.9 (±166)160.8 (±194)0.80 Fruit and vegetable consumption (cups per day)3 (±1)3 (±1)3 (±1)0.52 Dietary fat (% total kcal)35 (±4)34 (±4)35 (±4)0.033.

CONCLUSIONS

Accounting for all influencing characteristics, higher educational status was the only independent predictor of randomization. Perhaps, highly educated personnel are more invested in a military career, and thus, more concerned with consequences of failing required fitness tests. Thus, it may be important for future weight loss interventions to focus recruitment on less-educated personnel. Results suggest that weight loss interventions within a military population offer a unique opportunity to recruit a higher prevalence of males and individuals who identify as racial or ethnic minorities which are populations commonly underrepresented in weight loss research.

Qualitative perceptions of and preferences for the research process among patients with eating disorders

OBJECTIVE

Low participation and retention rates are persistent problems in eating disorder (ED) research. In order to improve the research process, this study used a qualitative approach to examine factors promoting and limiting research study participation among patients with EDs, and their preferences during research.

METHOD

Five 90-min focus groups were conducted with adult women (N = 29) enrolled at a residential ED treatment facility. Facilitators asked a series of open-ended questions about participants' experiences, opinions, and preferences with regard to ED treatment research. Transcript analysis identified themes using a consensual qualitative research approach.

RESULTS

It was revealed that preventing others' suffering, improving ED treatment, and having low participant burden were major themes facilitating research participation. Major barriers to research participation included concern that research interferes with self-care/recovery, burdensome nature of study design, and demeanor of the researchers/institutions involved with the study. Patients believed that the format of research assessments could be improved by better assessing the nuances of ED behaviors, examining non-ED outcomes, and including more open-ended questions. Patients anticipated that challenges in recovery, feelings of guilt, and logistical barriers could interfere with their ability to complete follow-up research assessments.

DISCUSSION

Factors related to the recruitment process, assessment format, follow-up methods, and communication throughout the research process may need to be addressed to increase participation and retention rates. Findings indicate that recruitment strategies should include emphasizing the broader impact of the research and increasing sensitivity to the nature of patients with EDs experiences.

Cost analysis and efficacy of recruitment strategies used in a large pragmatic community-based clinical trial targeting low-income seniors: a comparative descriptive analysis

OBJECTIVE

One of the most challenging parts of running clinical trials is recruiting enough participants. Our objective was to determine which recruitment strategies were effective in reaching specific subgroups.

STUDY DESIGN AND SETTING

We assessed the efficacy and costs of the recruitment strategies used in the Assessing Outcomes of Enhanced Chronic Disease Care Through Patient Education and a Value-based Formulary Study (ACCESS) in Alberta, Canada.

RESULTS

Twenty percent of the study budget ($354,330 CAD) was spent on recruiting 4013 participants, giving an average cost per enrolled of $88 CAD. Pharmacies recruited the most participants (n = 1217), at a cost of $128/enrolled. "Paid media" had the highest cost ($806/enrolled), whereas "word of mouth" and "unpaid media" had the lowest (~$3/enrolled). Participants enrolled from "seniors outreach" had the lowest baseline quality of life and income, while participants from "word of mouth" had the lowest educational attainment.

CONCLUSION

The "health care providers" strategies were especially successful - at a moderate cost per enrolled. The "media" strategies were less effective, short lasting, and more costly. No strategy was singularly effective in recruiting our targeted groups, emphasizing the importance of utilizing a variety of strategies to reach recruitment goals.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02579655 . Registered on 19 October 2015.

Guideline implementation in the Canadian chiropractic setting: a pilot cluster randomized controlled trial and parallel study

Background

Feasibility and pilot studies are recommended prior to embarking on large-scale costly confirmatory trials. The objectives were to determine the feasibility of conducting a cluster randomized controlled trial (C-RCT) to evaluate a complex knowledge translation (KT) intervention to improve the management of people with neck pain, and to identify challenges and potential solutions to conducting a fully powered C-RCT in the chiropractic setting.

Methods

Pilot C-RCT involving a nationally representative sample of chiropractors and patients. We invited 400 chiropractors and 150 patients to participate. Clinicians were randomized to receive either an online theory-based KT educational and brief action plan (BAP) intervention (intervention group) or a copy of a clinical practice guideline (control group). Study-related challenges were ascertained via mid-study phone interviews and end-of-study feedback questionnaires. Analyses focused on descriptive estimates of likely recruitment, retention, and adherence rates, and documentation of potential barriers.

Results

In total, 47 chiropractors (12%) agreed to participate and were randomized after resampling. Fifteen withdrew from the study, leaving a total of 32 (8%) participants. Eleven chiropractors in the intervention group completed the webinars and e-learning modules, two partially completed them and three did not register. Participating chiropractors recruited a total of 29 patients. Sixty-three percent (n = 7) of intervention and 56% (n = 10) of control group patients completed all outcome measures at both baseline and 3-months follow-up, attended follow-up visits and performed home exercises. Patients in the intervention group reported significant reductions in pain (mean 1.6, 95% CI 0.26–2.94, P = 0.027) and disability scores (9.8, 95% CI 3.68–15.91, P = 0.033) from baseline to 3-month follow-up. Key barriers to participation reported by chiropractors included lack of time, difficulties in recruiting patients, problems with the administration of study questionnaires, concern that the clinician-patient relationship might be jeopardized, and lack of assistance from office staff. Over half (55%) of the respondents in the intervention group encountered some difficulty registering or completing the educational modules.

Conclusion

Recruitment of clinicians and patients for a trial of a complex intervention can be challenging, and retention of participants after enrolment may be low. Future trials of this nature likely require multiple recruitment strategies to achieve desired sample sizes. Moreover, time-constraint issues are perceived particularly by clinicians as a major barrier to both study enrolment before, and protocol adherence during, their actual participation in a trial.

Trial registration

The study was registered at, NCT02483091, on 17th June 2015.

Electronic supplementary material

The online version of this article (10.1186/s12998-019-0253-z) contains supplementary material, which is available to authorized users.

Influence of subsidies and promotional strategies on outcomes in a beneficiary-based commercial weight-loss programme

To determine whether initial engagement, continued participation, and weight loss vary by subsidy and promotional strategies in a beneficiary-based, commercial weight-loss programme. We conducted a retrospective analysis of data from 2013 to 2016. Our dependent variables included initial engagement (≥1 calls; ≥2 weights), coach calls and weight change. Our independent variables were subsidy strategy (total subsidy (n = 9) vs cost sharing (n = 3)) and combination of promotional-subsidy strategies (mixed campaign + total subsidy (n = 6) vs mass media + total subsidy (n = 3)). We used logistic and linear regression analyses adjusted for beneficiary factors and clustering by organization. From 12 participating organizations, 26 068 beneficiaries registered of which 6215 initially engaged. Cost sharing was associated with significantly greater initial engagement as compared to total subsidy (OR 3.73, P < 0.001); however, no significant between-group differences existed in calls or weight change. Mass media + total subsidy group had significantly greater calls and weight loss at 12 months compared to mixed campaign + total subsidy (-2.6% vs -1.8%, P = 0.04). Cost sharing may promote greater initial engagement, although does not contribute to better participation or weight loss relative to total subsidy. If organizations elect total subsidy, then pairing this strategy with a mass media campaign may promote greater participation and weight loss among beneficiaries.

Who says "no" to participating in stroke clinical trials and why: an observational study from the Vancouver Stroke Program

BACKGROUND

Successful stroke trials require adequate recruitment. In this observational study, we assessed reasons for refusal to provide informed consent in eligible patients approached for clinical trial participation at the Vancouver Stroke Program.

METHODS

We assessed screening logs from four trials that were actively recruiting at our center: three randomized trials, two of which investigated different antithrombotic strategies for secondary prevention (NAVIGATE-ESUS, NCT02313909 12/2014; DATAS-II, NCT02295826 11/2014) and one that investigated surgery plus medical management versus medical management alone for primary prevention (CREST-2, NCT02089217 03/2014). The fourth study was observational and non-randomized; all participants received an external monitoring device (PROPHECY, NCT03712865 10/2018). Screening logs from June 2015 to April 2017 were reviewed retrospectively. Subsequently, we used a prospective structured case report form for screening (May 2017-March 2018). We assessed and compared refusal rates between trials, demographics of those refusing consent, and their reasons for doing so. We used descriptive statistics, chi-square and Fisher's exact tests as appropriate for non-parametric data, and t-tests for parametric data. We examined likelihood of refusal by sex using multivariable logistic regression models including age and trial intervention as co-variables.

RESULTS

A total of 235 patients (43% women) were approached for consent. More patients refused the surgical (59%) and antithrombotic trials (53%) compared with the non-randomized external monitoring device study (13%) (p < 0.001). Surgical trial refusals were primarily due to a desire for certainty in receiving a particular intervention (39%), with the majority of those patients wanting surgery. Refusals for the antithrombotic trials were mainly due to concerns with the potential side effects of the study drug (41%); refusals in the device trial were mainly due to disinterest (46%). Women refused participation more often than men (48% vs 33%). Women remained less likely to consent than men, even after adjustment for age and trial intervention (OR 0.46, 95% CI 0.26-0.82, p = 0.009).

CONCLUSIONS

Concern surrounding drug safety, randomization, and disinterest were the chief deterrents to enrolment; there were also differences in rates of consent by gender. A better understanding of why patients refuse participation in stroke trials may help to develop future patient-directed communication strategies to improve enrolment. Further research is required to better understand the reasons underlying gender disparities in consent rates.

Intravenous Fluid to Prevent Hypotension in Patients Undergoing Elective Colonoscopy

Colonoscopy may be associated with hypotension during sedation leading to postoperative morbidity. However, no treatment is proven to ameliorate intraoperative hypotension for this procedure. We therefore conducted a randomized trial to determine the effect of intravenous fluid infusion on the incidence of hypotension during sedation for colonoscopy. With institutional approval, 160 patients presenting for elective colonoscopy were randomized to 1.5 ml/kg or 15 ml/kg Hartmann's solution before colonoscopy. All observers were blind to group allocation. The incidence of hypotension during sedation (29% vs 25%; P=0.59) and postoperative morbidity (nausea, vomiting, headache, drowsiness and dizziness) (41% vs 39%; P=0.75) did not differ between the two groups. Hypotensive patients were older, had a higher baseline systolic blood pressure, and were thirstier after fluid infusion than normotensive patients. This study does not support the use of 15 ml/kg Hartmann's solution to reduce the incidence of hypotension or postoperative morbidity in patients undergoing elective colonoscopy.

Systematic review showed that stepped-wedge cluster randomized trials often did not reach their planned sample size

OBJECTIVE

To determine how often stepped-wedge cluster randomized controlled trials reach their planned sample size, and what reasons are reported for choosing a stepped-wedge trial design.

STUDY DESIGN AND SETTING

We conducted a PubMed literature search (period 2012 to 2017) and included articles describing the results of a stepped-wedge cluster randomized trial. We calculated the percentage of studies reaching their prespecified number of participants and clusters, and we summarized the reasons for choosing the stepped-wedge trial design as well as difficulties during enrollment.

RESULTS

Forty-six individual stepped-wedge studies from a total of 53 articles were included in our review. Of the 35 studies, for which recruitment rate could be calculated, 69% recruited their planned number of participants, with 80% having recruited the planned number of clusters. Ethical reasons were the most common motivation for choosing the stepped-wedge trial design. Most important difficulties during study conduct were dropout of clusters and delayed implementation of the intervention.

CONCLUSION

About half of recently published stepped-wedge trials reached their planned sample size indicating that recruitment is also a major problem in these trials. Still, the stepped-wedge trial design can yield practical, ethical, and methodological advantages.

The Use of Web-Based Technologies in Health Research Participation: Qualitative Study of Consumer and Researcher Experiences

BACKGROUND

Health consumers are often targeted for their involvement in health research including randomized controlled trials, focus groups, interviews, and surveys. However, as reported by many studies, recruitment and engagement of consumers in academic research remains challenging. In addition, there is scarce literature describing what consumers look for and want to achieve by participating in research.

OBJECTIVE

Understanding and responding to the needs of consumers is crucial to the success of health research projects. In this study, we aim to understand consumers' needs and investigate the opportunities for addressing these needs with Web-based technologies, particularly in the use of Web-based research registers and social networking sites (SNSs).

METHODS

We undertook a qualitative approach, interviewing both consumer and medical researchers in this study. With the help from an Australian-based organization supporting people with musculoskeletal conditions, we successfully interviewed 23 consumers and 10 researchers. All interviews were transcribed and analyzed with thematic analysis methodology. Data collection was stopped after the data themes reached saturation.

RESULTS

We found that consumers perceive research as a learning opportunity and, therefore, expect high research transparency and regular updates. They also consider the sources of the information about research projects, the trust between consumers and researchers, and the mobility of consumers before participating in any research. Researchers need to be aware of such needs when designing a campaign for recruitment for their studies. On the other hand, researchers have attempted to establish a rapport with consumer participants, design research for consumers' needs, and use technologies to reach out to consumers. A systematic approach to integrating a variety of technologies is needed.

CONCLUSIONS

On the basis of the feedback from both consumers and researchers, we propose 3 future directions to use Web-based technologies for addressing consumers' needs and engaging with consumers in health research: (1) researchers can make use of consumer registers and Web-based research portals, (2) SNSs and new media should be frequently used as an aid, and (3) new technologies should be adopted to remotely collect data and reduce administrative work for obtaining consumers' consent.

Two-step recruitment process optimizes retention in FLEX clinical trial

Introduction

The Flexible Lifestyle Empowering Change Study (FLEX) is a multi-site randomized controlled trial to test the efficacy of an adaptive behavioral intervention to promote self-management and improve glycemic control for adolescents with type 1 diabetes mellitus. A two-step recruitment process was used to optimize study retention by facilitating informed decision-making regarding participation.

Methods

Those who expressed interest at first contact were given more detailed study information followed by telephone calls to the adolescents and their parents to answer questions and explore potential barriers to participation before making a decision regarding study enrollment.

Results

Of 694 eligible adolescents who were invited to participate, 397 (57.2%) expressed interest when initially contacted (Step 1). Upon completion of the follow-up telephone calls (Step 2), 276 (39.8%) still agreed to participate; and 258 (37.2%) enrolled and completed a baseline visit with a parent/guardian. Completion rates for measurement visits remained high throughout the study, with an end-of-study retention rate of 93.4%; and only 12 (4.7%) families withdrew from the study.

Conclusion

The two-step recruitment process encourages potential participants to thoughtfully evaluate their willingness to participate, as well as their ability to make a commitment to the full completion of study requirements. When demonstrating the efficacy of a randomized controlled trial, it may be preferable to accept lower recruitment rates in order to optimize retention rates. The additional time and effort required to implement this two-step process is worthwhile. With a high retention rate, we can be more confident that the outcomes of the randomized controlled trial actually reflect the impact of the intervention.

Factors associated with clinical trials that fail and opportunities for improving the likelihood of success: A review

Clinical trials are time consuming, expensive, and often burdensome on patients. Clinical trials can fail for many reasons. This survey reviews many of these reasons and offers insights on opportunities for improving the likelihood of creating and executing successful clinical trials. Literature from the past 30 years was reviewed for relevant data. Common patterns in reported successful trials are identified, including factors regarding the study site, study coordinator/investigator, and the effects on participating patients. Specific instances where artificial intelligence can help improve clinical trials are identified.

A Curated Cancer Clinical Outcomes Database (C3OD) for accelerating patient recruitment in cancer clinical trials

Data used to determine patient eligibility for cancer clinical trials often come from disparate sources that are typically maintained by different groups within an institution, use differing technologies, and are stored in different formats. Collecting data and resolving inconsistencies across sources increase the time it takes to screen eligible patients, potentially delaying study completion. To address these challenges, the Biostatistics and Informatics Shared Resource at The University of Kansas Cancer Center developed the Curated Cancer Clinical Outcomes Database (C3OD). C3OD merges data from the electronic medical record, tumor registry, bio-specimen and data registry, and allows querying through a single unified platform. By centralizing access and maintaining appropriate controls, C3OD allows researchers to more rapidly obtain detailed information about each patient in order to accelerate eligibility screening. This case report describes the design of this informatics platform as well as initial assessments of its reliability and usability.

Unsupervised online neuropsychological test performance for individuals with mild cognitive impairment and dementia: Results from the Brain Health Registry

INTRODUCTION

The purpose of this study is to compare online neuropsychological test performance of older adults across self-reported diagnoses of being cognitively normal, mild cognitive impairment, and dementia due to Alzheimer's disease and to determine the association of memory concerns and family history of dementia on cognitive performance.

METHODS

Participants completed the Cogstate Brief Battery unsupervised at home.

RESULTS

Data from 6463 participants over the age of 55 years were analyzed. Adults with the diagnosis of mild cognitive impairment and Alzheimer's disease were associated with poorer performance on all cognitive tests than cognitively normal adults (P < .05 for all), and online cognitive test performance significantly improved diagnostic classification (P < .001). Poorer performance on all cognitive measures was associated with memory concern (P < .001 for all) but not family history of dementia.

DISCUSSION

Our results provide preliminary support for the use of cognitive tests taken online without supervision as a means to improve the efficiency of participant screening and recruitment for clinical trials.

Sex and cardiovascular disease status differences in attitudes and willingness to participate in clinical research studies/clinical trials

BACKGROUND

While women are under-represented in research on cardiovascular disease (CVD), little is known about the attitudes of men and women with CVD regarding participation in clinical research studies/clinical trials.

METHODS

Patients with CVD (and/or risk factors) and patients with other chronic conditions from Iowa were recruited from a commercial panel. An on-line survey assessed willingness to participate (WTP) and other attitudes towards aspects of clinical research studies.

RESULTS

Based on 504 respondents, there were no differences in WTP in patients with CVD compared to patients with other chronic diseases. Across all respondents, men had 14% lower WTP (relative risk (RR) for men, 0.86, 95% CI, 0.72-1.02). Among patients with CVD, there was no significant difference in WTP between women (RR for women = 1) and men (RR for men, 0.96, 95% CI, 0.82-1.14). There were no significant differences based on sex or CVD status for attitudes on randomization, blinding, side effects, conflict of interest, experimental treatments or willingness to talk to one's physician. Women had more favorable attitudes about participants being treated like "guinea pigs" (RR for men, 0.84, 95% CI, 0.73-0.98) and clinical trials being associated with terminally ill patients (RR for men, 0.93, 95% CI, 0.86-1.00).

CONCLUSIONS

The findings reported here suggest that the observed lower levels of participation by women are due to factors other than a lower WTP or to women having more negative attitudes towards aspects of study participation. Patients with CVD have similar attitudes and WTP as patients with other chronic conditions.

Intensive spa and exercise therapy program for returning to work for low back pain patients: a randomized controlled trial

We aimed to determine whether a 5-day intensive inpatient spa and exercise therapy and educational program is more effective than usual care in improving the rate of returning to work at 1 year for patients with subacute and chronic low back pain (LBP) on sick leave for 4 to 24 weeks. We conducted a 12-month randomized controlled trial. LBP patients were assigned to 5-day spa (2 hr/day), exercise (30 min/day) and education (45 min/day) or to usual care. The primary outcome was the percentage of patients returning to work at 1 year after randomization. Secondary outcomes were pain, disability and health-related quality of life at 1 year and number of sick leave days from 6 to 12 months. The projected recruitment was not achieved. Only 88/700 (12.6%) patients planned were enrolled: 45 in the spa therapy group and 43 in the usual care group. At 1 year, returning to work was 56.3% versus 41.9% (OR 1.69 [95% CI 0.60-4.73], p = 0.32) respectively. There was no significant difference for any of the secondary outcomes. However, our study lacked power.

A survey of practices for the use of electronic health records to support research recruitment

Electronic health records (EHRs) provide great promise for identifying cohorts and enhancing research recruitment. Such approaches are sorely needed, but there are few descriptions in the literature of prevailing practices to guide their use. A multidisciplinary workgroup was formed to examine current practices in the use of EHRs in recruitment and to propose future directions. The group surveyed consortium members regarding current practices. Over 98% of the Clinical and Translational Science Award Consortium responded to the survey. Brokered and self-service data warehouse access are in early or full operation at 94% and 92% of institutions, respectively, whereas, EHR alerts to providers and to research teams are at 45% and 48%, respectively, and use of patient portals for research is at 20%. However, these percentages increase significantly to 88% and above if planning and exploratory work were considered cumulatively. For most approaches, implementation reflected perceived demand. Regulatory and workflow processes were similarly varied, and many respondents described substantive restrictions arising from logistical constraints and limitations on collaboration and data sharing. Survey results reflect wide variation in implementation and approach, and point to strong need for comparative research and development of best practices to protect patients and facilitate interinstitutional collaboration and multisite research.

EliIE: An open-source information extraction system for clinical trial eligibility criteria

OBJECTIVE

To develop an open-source information extraction system called Eligibility Criteria Information Extraction (EliIE) for parsing and formalizing free-text clinical research eligibility criteria (EC) following Observational Medical Outcomes Partnership Common Data Model (OMOP CDM) version 5.0.

MATERIALS AND METHODS

EliIE parses EC in 4 steps: (1) clinical entity and attribute recognition, (2) negation detection, (3) relation extraction, and (4) concept normalization and output structuring. Informaticians and domain experts were recruited to design an annotation guideline and generate a training corpus of annotated EC for 230 Alzheimer's clinical trials, which were represented as queries against the OMOP CDM and included 8008 entities, 3550 attributes, and 3529 relations. A sequence labeling-based method was developed for automatic entity and attribute recognition. Negation detection was supported by NegEx and a set of predefined rules. Relation extraction was achieved by a support vector machine classifier. We further performed terminology-based concept normalization and output structuring.

RESULTS

In task-specific evaluations, the best F1 score for entity recognition was 0.79, and for relation extraction was 0.89. The accuracy of negation detection was 0.94. The overall accuracy for query formalization was 0.71 in an end-to-end evaluation.

CONCLUSIONS

This study presents EliIE, an OMOP CDM-based information extraction system for automatic structuring and formalization of free-text EC. According to our evaluation, machine learning-based EliIE outperforms existing systems and shows promise to improve.

Willingness to participate in pragmatic dialysis trials: the importance of physician decisional autonomy and consent approach

BACKGROUND

Pragmatic clinical trials embedded in routine delivery of clinical care can lead to improvements in quality of care, but often have design features that raise ethical concerns.

METHODS

We performed a discrete choice experiment and used conjoint analysis to assess how specific attributes of pragmatic dialysis trials influenced patients' and physicians' willingness to have their dialysis facility participate in a hypothetical trial of hypertension management. Electronic survey data were collected from 200 patients enrolled from 11 outpatient hemodialysis units and from 203 nephrologists. The three attributes studied were physicians' treatment autonomy, participants' research burden, and the approach to consent. The influence of each attribute was quantified using mixed-effects logistic regression.

RESULTS

Similar proportions of patients were willing to have their facilities participate in a trial with high vs. low physician autonomy (77% vs. 79%; p = 0.13) and research burden (76% vs. 80%; p = 0.06). Opt-in, opt-out, and notification-only consent approaches were acceptable to most patients (84%, 82%, and 81%, respectively), but compared to each of these consent approaches, fewer patients (66%) were willing to have their facility participate in a trial that used no notification (p < 0.001 for each 2-way comparison). Among the physicians, similar proportions were willing to participate in trials with high and low physician autonomy (61% and 61%, respectively, p = 0.96) or with low and high burden (60 and 61%, respectively, p = 0.79). However, as for the patients, the consent approach influenced trial acceptability with 77%, 69%, and 62% willing to participate using opt-in, opt-out, and notification-only, respectively, compared to no notification (36%) (p < 0.001 for each 2-way comparison).

CONCLUSIONS

Curtailing physician's treatment autonomy and increasing the burden associated with participation did not influence patients' or physicians' willingness to participate in the hypothetical research, suggesting that pragmatic dialysis trials are generally acceptable to patients and physicians. Both patients and physicians preferred consent approaches that include at least some level of patient notification, but the majority of patients were still willing to participate in trials that did not notify patients of the research.