Factors influencing recruitment and retention of participants in clinical studies conducted at a tertiary referral center: A five-year audit

Screen Failures in Clinical Trials in Retina

PURPOSE

Disparities in clinical trials are a major problem because of significant underrepresentation of certain gender, racial, and ethnic groups. Several factors including stringent eligibility criteria and recruitment strategies hinder our understanding of retinal disease. Thus, we aimed to study the various reasons of screen failures and specific patient and study characteristics among screen failures.

DESIGN

This is a cross-sectional retrospective study.

METHODS

Screening data of 87 trials from 6 centers were analyzed. Study characteristics (disease studied, phase of trial, and route of drug administration) and patient demographics (age, gender, race, ethnicity, and employment status) were compared among different causes of screen failures. Screen failures were broadly classified into 6 categories: exclusion because of vision-based criteria, exclusion because of imaging findings, exclusion because of other factors, patient-related criteria, physician-related criteria, and miscellaneous. Descriptive statistics, Pearson chi-square test, and analysis of variance were used for statistical analysis.

MAIN OUTCOME MEASURES

Prevalence of various reasons for screen failures in multiple trials and its trend among different study and patient characteristics.

RESULTS

Among 87 trials and 962 patients, 465 (48.2%) patients were successfully randomized and 497 (51.8%) patients were classified as screen failures. The trials were conducted for various retinal diseases. Mean age was 76.50 ± 10.45 years and 59.4% were females. Predominantly White patients (93.4%) and unemployed/retired patients (66.6%) were screened. Of the 497 screen failures, most were because of patients not meeting inclusion criteria of imaging findings (n = 221 [44.5%]) followed by inclusion of vision-based criteria (n = 73 [14.7%]), exclusion because of other factors (n = 75 [15.1%]), patient-related (n = 34 [6.8%]), physician-related (n = 28 [5.6%]), and miscellaneous reasons (n = 39 [7.8%]). Reason for screen failure was not available for 27 (5.4%) patients. A higher proportion of patients screened for surgical trials (15%) declined to participate in the study compared with noninvasive trials involving topical drugs and photobiomodulation (0%) (P = 0.02).

CONCLUSIONS

Patients not meeting the imaging and vision-cased criteria were the most common reasons for screen failures. White patients and unemployed patients predominantly participated in clinical trials. Patients are more inclined to continue participation in noninvasive clinical trials compared with surgical trials. Better recruitment strategies and careful consideration of study criteria can aid in decreasing the rate of screen failures.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references in the Footnotes and Disclosures at the end of this article.

Feasibility of a Randomized, Interventional Pilot Clinical Study of Oral Cannabinoids in People with HIV on Antiretroviral Therapy: CTNPT 028

Cannabis-based medicines (CBMs) could help reduce systemic inflammation in people with HIV (PWH). In a prospective, randomized pilot study we enrolled participants from August 2021-April 2022 with HIV, aged ≥18 and on antiretroviral therapy and randomly assigned them to cannabidiol (CBD) ± Δ9-tetrahydrocannabinol (THC) capsules for 12 weeks with the primary objective being to assess safety and tolerability. Here we report on timeliness to study initiation, enrolment, compliance and retention rates. The target sample size was not reached. Two hundred and five individuals were approached, and 10 consented and were randomized; the rest refused (reasons: cannabis-related stigma/discomfort; too many study visits/insufficient time; unwillingness to undergo a "washout period" for three weeks) or were not eligible. The age of those randomized was 58 years (IQR 55-62); 80% were male. Only three met all criteria (30% enrolment compliance); seven were enrolled with minor protocol deviations. Compliance was excellent (100%). Eight (80%) participants completed the study; two (20%) were withdrawn for safety reasons (transaminitis and aggravation of pre-existing anemia). Time to study initiation and recruitment were the most challenging aspects. Ongoing work is required to reduce stigma related to CBMs. Future studies should find a balance between the requirements for safety monitoring and frequency of study visits.

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.

Participant characteristics and exclusion from phase 3/4 industry funded trials of chronic medical conditions: meta-analysis of individual participant level data

Objectives

To assess whether age, sex, comorbidity count, and race and ethnic group are associated with the likelihood of trial participants not being enrolled in a trial for any reason (ie, screen failure).

Design

Bayesian meta-analysis of individual participant level data.

Setting

Industry funded phase 3/4 trials of chronic medical conditions.

Participants

Participants were identified using individual participant level data to be in either the enrolled group or screen failure group. Data were available for 52 trials involving 72 178 screened individuals of whom 24 733 (34%) were excluded from the trial at the screening stage.

Main outcome measures

For each trial, logistic regression models were constructed to assess likelihood of screen failure in people who had been invited to screening, and were regressed on age (per 10 year increment), sex (male v female), comorbidity count (per one additional comorbidity), and race or ethnic group. Trial level analyses were combined in Bayesian hierarchical models with pooling across condition.

Results

In age and sex adjusted models across all trials, neither age nor sex was associated with increased odds of screen failure, although weak associations were detected after additionally adjusting for comorbidity (odds ratio of age, per 10 year increment was 1.02 (95% credibility interval 1.01 to 1.04) and male sex (0.95 (0.91 to 1.00)). Comorbidity count was weakly associated with screen failure, but in an unexpected direction (0.97 per additional comorbidity (0.94 to 1.00), adjusted for age and sex). People who self-reported as black seemed to be slightly more likely to fail screening than people reporting as white (1.04 (0.99 to 1.09)); a weak effect that seemed to persist after adjustment for age, sex, and comorbidity count (1.05 (0.98 to 1.12)). The between-trial heterogeneity was generally low, evidence of heterogeneity by sex was noted across conditions (variation in odds ratios on log scale of 0.01-0.13).

Conclusions

Although the conclusions are limited by uncertainty about the completeness or accuracy of data collection among participants who were not randomised, we identified mostly weak associations with an increased likelihood of screen failure for age, sex, comorbidity count, and black race or ethnic group. Proportionate increases in screening these underserved populations may improve representation in trials.

Trial registration number

PROSPERO CRD42018048202.

Audit of screen failure in 15 randomised studies from a low and middle-income country

Background

Growth and development in patient management occurs via randomised studies. Screen failure is a significant hurdle while conducting randomised studies. There is limited data available from low and middle-income countries about factors resulting in screen failure. Hence, this audit was performed to identify the proportion of patients who screen failed and to elucidate reasons for the same.

Methods

This was an audit of 15 randomised studies performed by medical oncology solid tumour unit II of Tata Memorial Centre. The screening logs of these studies were acquired. From the screening logs, data regarding the number of patients who had screen failed & reason for the same were obtained. Descriptive statistics were performed.

Results

A total of 7,481 patients were screened for 15 randomised clinical studies. Out of these, 3,666 (49.0%) patients were enrolled into trials and 3,815 (51.0%) screen failed. The most common reason for screen failure was 'not meeting inclusion criteria' (54.9%) followed by declining to take treatment (22.2%). Other factors that affect enrolment were 'not willing to stay in the locality of the trial site' (6.2%), being recruited in other studies (3.7%), poor performance status (PS) (3.4%), non-compliance (2.2%), meeting exclusion criteria (0.9%) and 'other' (6.5%).

Conclusion

The commonest causes of screen failure in lower and middle-income countries are non-meeting of inclusion criteria followed by declining to take treatment, not willing to stay in locality of trial site, recruited into other studies, poor PS, non-compliance, meeting exclusion criteria & 'other'. This information would help analysing and hence planning of newer strategies to decrease the rate of screen failure.

Virtual engagement of under-resourced communities: Lessons learned during the COVID-19 pandemic for creating crisis-resistant research infrastructure

The COVID-19 pandemic led to an increased need to conduct research and community engagement using digital methods. Unfortunately, the shift away from in-person research activities can make it difficult to engage and recruit participants from under-resourced communities that lack adequate digital infrastructure. At the beginning of the pandemic, our team recognized that imminent lockdowns would significantly disrupt ongoing engagement with low-income housing resident community partners and that we would ultimately bear responsibility if that occurred. This manuscript outlines the development of methods designed to create capacity for virtual engagement with a community advisory board that were subsequently applied to a longitudinal mixed-methods study. We describe how our experience engaging low-income housing residents during the height of the pandemic influenced the approach and offer guidelines useful for engaging under-resourced communities regardless of setting. Of these, a strong commitment to providing technology, unlimited data connectivity, and basic digital literacy training/technical support is most important. While each of these is essential and failure in any one area will reduce overall effectiveness of the effort, providing adequate technical support while maintaining ongoing relationships with community members is the most important and resource-intensive.