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Evaluation of active and passive recruitment methods used in randomized controlled trials targeting pediatric obesity
Hollie A Raynor1, Kathrin M Osterholt, Chantelle N Hart
1The Warren Alpert Medical School of Brown University, Providence, RI, USA. hraynor@utk.edu
Insights
Active recruitment methods like pediatrician referrals and targeted mailings are most effective for pediatric obesity trials. Combining multiple strategies is recommended for successful participant enrollment and randomization.
Area of Science:
- Pediatric obesity research
- Clinical trial recruitment strategies
- Health intervention studies
Background:
- Two pediatric obesity intervention trials (NCT00259324, NCT00200265) required evaluation of recruitment methods.
- Understanding enrollment dynamics is crucial for the success of pediatric clinical trials.
Purpose of the Study:
- To compare active versus passive recruitment methods in pediatric obesity trials.
- To evaluate enrollment numbers, randomization rates, costs, and cost-effectiveness.
- To identify optimal strategies for recruiting parent-child dyads.
Main Methods:
- Recruitment methods categorized as active (pediatrician referral, targeted mailings) or passive (mass media, community outreach, word-of-mouth).
- Monitored enrollment, randomization, and costs (staff time, mileage, direct costs) over 22 months.
- Calculated cost per randomized family for each method.
Main Results:
- Active methods, particularly pediatrician referral and targeted mailings, enrolled 87.2% of randomized families.
- Passive methods showed better retention from enrollment to randomization (p<0.05) but yielded only 21 families.
- Total recruitment cost was ~$91,000, with a cost per randomized family of $554.77. Pediatrician referral was most cost-effective ($145.95/family) but yielded fewer participants.
Conclusions:
- Active recruitment strategies (pediatrician referral, targeted mailings) are most successful for pediatric obesity trials.
- Recruitment requires significant resources, necessitating a multi-pronged approach.
- Combining diverse recruitment strategies is recommended for maximizing participant enrollment in pediatric research.
Objective:
Evaluate enrollment numbers, randomization rates, costs, and cost-effectiveness of active versus passive recruitment methods for parent-child dyads into two pediatric obesity intervention trials.
Methods:
Recruitment methods were categorized into active (pediatrician referral and targeted mailings, with participants identified by researcher/health care provider) versus passive methods (newspaper, bus, internet, television, and earning statements; fairs/community centers/schools; and word of mouth; with participants self-identified). Numbers of enrolled and randomized families and costs/recruitment method were monitored throughout the 22-month recruitment period. Costs (in USD) per recruitment method included staff time, mileage, and targeted costs of each method.
Results:
A total of 940 families were referred or made contact, with 164 families randomized (child: 7.2+/-1.6 years, 2.27+/-0.61 standardized body mass index [zBMI], 86.6% obese, 61.7% female, 83.5% Caucasian; parent: 38.0+/-5.8 years, 32.9+/-8.4 BMI, 55.2% obese, 92.7% female, 89.6% caucasian). Pediatrician referral, followed by targeted mailings, produced the largest number of enrolled and randomized families (both methods combined producing 87.2% of randomized families). Passive recruitment methods yielded better retention from enrollment to randomization (p<0.05), but produced few families (21 in total). Approximately $91,000 was spent on recruitment, with cost per randomized family at $554.77. Pediatrician referral was the most cost-effective method, $145.95/randomized family, but yielded only 91 randomized families over 22-months of continuous recruitment.
Conclusion:
Pediatrician referral and targeted mailings, which are active recruitment methods, were the most successful strategies. However, recruitment demanded significant resources. Successful recruitment for pediatric trials should use several strategies.
Clinical Trials Registration:
NCT00259324, NCT00200265.
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