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Online Patient Recruitment in Clinical Trials: Systematic Review and Meta-Analysis
Mette Brøgger-Mikkelsen1,2,3, Zarqa Ali1,2, John R Zibert3
1Department of Dermatology, Bispebjerg Hospital, Copenhagen, Denmark.
Background:
Recruitment for clinical trials continues to be a challenge, as patient recruitment is the single biggest cause of trial delays. Around 80% of trials fail to meet the initial enrollment target and timeline, and these delays can result in lost revenue of as much as US $8 million per day for drug developing companies.
Objective:
This study aimed to conduct a systematic review and meta-analysis examining the effectiveness of online recruitment of participants for clinical trials compared with traditional in-clinic/offline recruitment methods.
Methods:
Data on recruitment rates (the average number of patients enrolled in the study per month and per day of active recruitment) and conversion rates (the percentage of participants screened who proceed to enroll into the clinical trial), as well as study characteristics and patient demographics were collected from the included studies. Differences in online and offline recruitment rates and conversion rates were examined using random effects models. Further, a nonparametric paired Wilcoxon test was used for additional analysis on the cost-effectiveness of online patient recruitment. All data analyses were conducted in R language, and P<.05 was considered significant.
Results:
In total, 3861 articles were screened for inclusion. Of these, 61 studies were included in the review, and 23 of these were further included in the meta-analysis. We found online recruitment to be significantly more effective with respect to the recruitment rate for active days of recruitment, where 100% (7/7) of the studies included had a better online recruitment rate compared with offline recruitment (incidence rate ratio [IRR] 4.17, P=.04). When examining the entire recruitment period in months we found that 52% (12/23) of the studies had a better online recruitment rate compared with the offline recruitment rate (IRR 1.11, P=.71). For cost-effectiveness, we found that online recruitment had a significantly lower cost per enrollee compared with offline recruitment (US $72 vs US $199, P=.04). Finally, we found that 69% (9/13) of studies had significantly better offline conversion rates compared with online conversion rates (risk ratio 0.8, P=.02).
Conclusions:
Targeting potential participants using online remedies is an effective approach for patient recruitment for clinical research. Online recruitment was both superior in regard to time efficiency and cost-effectiveness compared with offline recruitment. In contrast, offline recruitment outperformed online recruitment with respect to conversion rate.
Insights
Online recruitment significantly improves clinical trial enrollment speed and cost-effectiveness. However, traditional offline methods show higher participant conversion rates, highlighting a trade-off in patient recruitment strategies.
Area of Science:
- Clinical research methodology
- Digital health and patient recruitment
- Evidence-based medicine and systematic reviews
Background:
- Patient recruitment is a major bottleneck in clinical trials, causing significant delays and financial losses.
- Approximately 80% of trials fail to meet enrollment targets, impacting drug development timelines.
- Delays can cost drug development companies up to $8 million daily.
Purpose of the Study:
- To systematically review and meta-analyze the effectiveness of online versus traditional in-clinic/offline participant recruitment for clinical trials.
- To compare recruitment rates, conversion rates, and cost-effectiveness between online and offline methods.
Main Methods:
- Systematic review and meta-analysis of studies comparing online and offline clinical trial recruitment.
- Data collection included recruitment rates (per month/day) and conversion rates (screened to enrolled).
- Random effects models were used for rate comparisons; Wilcoxon test for cost-effectiveness analysis; R language for statistical analysis.
Main Results:
- Online recruitment demonstrated significantly higher rates per active recruitment day (IRR 4.17, P=.04).
- Online recruitment was significantly more cost-effective, with a lower cost per enrollee ($72 vs. $199, P=.04).
- Offline recruitment showed significantly better conversion rates (risk ratio 0.8, P=.02).
Conclusions:
- Online recruitment strategies are effective for clinical research, offering superior time efficiency and cost-effectiveness.
- Offline recruitment methods remain more effective for converting screened individuals into enrolled participants.
- The choice between online and offline recruitment depends on trial-specific priorities regarding speed, cost, and conversion rates.
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