Original articleRecruitment for controlled clinical trials: Literature summary and annotated bibliography
Abstract
This article is a literature summary and annotated bibliography of research on recruitment for controlled clinical trials published through 1995. It extends and revises a similar review published in this journal a decade ago. The current commentary focuses on intervening developments in recruitment, including diverse populations, HIV trials, primary prevention trials, recruitment strategies, overall planning and management, patient and physician attitudes, adherence, generalizability, and cost. Profound barriers may exist in the recruitment of diverse populations, involving language, cultural factors, beliefs about medical research, and the appropriateness of available protocols. Extensive literature exists on patient and physician barriers to participation. Trials in HIV-infected or AIDs-diagnosed individuals introduce special considerations, including issues of confidentiality, parallel track design, and populations difficult to define and track. Recruitment strategies such as patient registries, occupational screening, direct mail, and the media are now prominent in the literature. Successful planning and management of an overall recruitment plan include piloting strategies, monitoring recruitment by data tracking systems, and hiring quality staff. Generalizability of study results is influenced by the characteristics of participants and by their adherence to study protocol. With increasingly limited funding to conduct clinical trials, efforts to quantify and reduce recruitment costs are being made. While over 4000 titles were identified, primarily by MEDLINE literature search, the articles summarized emphasize data-supported and- confirmed conclusions, and broad coverage of disease areas. We annotate here 91 outstanding articles useful for formulation of overall recruitment approaches in clinical trials.
References (7)
- S Hertert et al.
Community volunteers as recruitment staff in a clinical trial: the systolic hypertension in the elderly program (SHEP) experience
Controlled Clin Trials
(1996) - D.B. Hunninghake et al.
Controlled Clin Trials
(1987) - L.M. Friedman et al.
Cited by (350)
Clinical preparation—subject recruitment
2023, Translational Radiation OncologyRandomized controlled trials are essential to improving patient outcomes; however, recruitment is a barrier to successful trial completion. Poor subject recruitment∗ and retention∗ limit generalizability, reliability, external validity and increase risk of type II error∗ and costs/resources).1 Studies suggest that less than a third of trials achieve initial recruitment targets and require extension and/or additional funds.2, 3, 4 Recruitment that includes a diverse population such as racial/ethnic minority groups, women, elderly, LGBTQ + members and vulnerable populations such as those living with HIV/AIDS is crucial to allow generalizability and minimization of health disparities in treatment outcomes. There are a multitude of barriers to successful recruitment to RCTs including lack of pre-trial planning, inadequate community outreach efforts, complex study trial design, restrictive eligibility criteria, and sociocultural barriers. In this chapter, we discuss interventions to improve subject recruitment and retention based on contemporary studies.
Assessment of Patients' Willingness to Participate in a Randomized Trial of Spinal versus General Anesthesia for Lumbar Spine Surgery
2022, World NeurosurgeryProspective 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.
To prospectively investigate patients' willingness to enroll in randomized trials of lumbar spine surgery under spinal versus general anesthesia and identify any potential barriers.
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.
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.
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.
Clinical trials: Cellular regenerative approaches
2022, Neural Repair and Regeneration after Spinal Cord Injury and Spine TraumaThis chapter will provide an overview of various cellular regenerative therapies currently being implemented in clinical trials for the treatment of spinal cord injury (SCI). These treatments involve stem cell transplantation of various neural cell subtypes that aim to help replenish the loss of cells at the site of injury, thus aiming to improve the locomotion and autonomy of SCI patients. Clinical trials from phases 1 through 3 were included, examining the study aims, conditions, inclusion criteria, and results, should they be provided. Clinical trials conducted in North America, Europe, Japan, and Australia are emphasized in this chapter.
Barriers and facilitators to the participation of subjects in clinical trials: An overview of reviews
2021, Contemporary Clinical Trials CommunicationsThe 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.
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.
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.
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.
A knowledge base of clinical trial eligibility criteria
2021, Journal of Biomedical InformaticsWe 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.
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.
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%.
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.
A survey of adult preferences regarding recruitment for pediatric research
2020, International Journal of Pediatric OtorhinolaryngologyAlthough 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.
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.
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).
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.