Retention of African-American and White youth in a longitudinal substance use study

Retention strategies in longitudinal cohort studies: a systematic review and meta-analysis

BACKGROUND

Participant retention strategies that minimise attrition in longitudinal cohort studies have evolved considerably in recent years. This study aimed to assess, via systematic review and meta-analysis, the effectiveness of both traditional strategies and contemporary innovations for retention adopted by longitudinal cohort studies in the past decade.

METHODS

Health research databases were searched for retention strategies used within longitudinal cohort studies published in the 10-years prior, with 143 eligible longitudinal cohort studies identified (141 articles; sample size range: 30 to 61,895). Details on retention strategies and rates, research designs, and participant demographics were extracted. Meta-analyses of retained proportions were performed to examine the association between cohort retention rate and individual and thematically grouped retention strategies.

RESULTS

Results identified 95 retention strategies, broadly classed as either: barrier-reduction, community-building, follow-up/reminder, or tracing strategies. Forty-four of these strategies had not been identified in previous reviews. Meta-regressions indicated that studies using barrier-reduction strategies retained 10% more of their sample (95%CI [0.13 to 1.08]; p = .01); however, studies using follow-up/reminder strategies lost an additional 10% of their sample (95%CI [- 1.19 to - 0.21]; p = .02). The overall number of strategies employed was not associated with retention.

CONCLUSIONS

Employing a larger number of retention strategies may not be associated with improved retention in longitudinal cohort studies, contrary to earlier narrative reviews. Results suggest that strategies that aim to reduce participant burden (e.g., flexibility in data collection methods) might be most effective in maximising cohort retention.

Recruiting African Americans with peripheral artery disease for a behavioral intervention trial

We report recruitment strategies for an NIH-funded trial focused on African Americans with peripheral artery disease (PAD). We present complete recruitment efforts for this 1-year trial, 5-year study. Eligibility included the following: African American, a resting ankle–brachial index (ABI) ⩽ 0.99, a short physical performance battery (SPPB) score of 10 or lower, English speaking, telephone access, and absence of coronary ischemia during a submaximal treadmill test. Recruitment included mailings of brochures to zip codes in which more than 50% of residents were African American, advertisements, community events, and physician/clinic referrals. We telephone-screened 3511 persons, of whom 792 did not recall the method by which they learned about the study. We randomized 174 participants. Mailings yielded the highest percentage of randomized participants ( n=60, 34.4%), followed by television advertisements ( n=42, 24.1%), followed by community events ( n=24, 13.8%). In conclusion, to recruit African Americans with PAD for a clinical trial, investigators should consider mailings of brochures, television advertisements, and community events. ClinicalTrials.gov Identifier: NCT01321086

Recruitment and retention of children in behavioral health risk factor studies: REACH strategies

BACKGROUND

Children are a common target group in behavioral health research. Yet their recruitment into community setting studies poses challenges to researchers and little guidance exists on recruitment and retention methods.

PURPOSE

This study aims to present successful strategies for the recruitment and retention of children into behavioral health risk factor studies.

METHOD

Firstly, a literature search in various databases was undertaken for papers published 1990-2012, focusing on recruitment and retention methods used in community-based studies with children aged 3-18 years. Secondly, a Delphi study was conducted in 2012 with 27 international experts in the fields of child-related behavioral health risk factors to gather expertise and consensus on successful recruitment and retention strategies applicable in children.

RESULTS

The literature review and Delphi study yielded a set of successful child recruitment and retention strategies, and examples for implementation. These are presented as strategies to Recruit, Engage and retAin Children in behavioral Health risk factor studies (REACH). Recognized strategies for successful recruitment and retention included building trustful relationships between researchers and study partners, parents, and children; having project champions; optimizing consent and follow-up procedures; offering incentives to study partners, children, and parents; minimizing participant burden; and designing feasible studies with cohesive research teams.

CONCLUSION

Using multiple REACH strategies is most promising for maximizing response rates and minimizing attrition of children in cross-sectional, longitudinal, and behavioral intervention studies in community settings such as schools, child care centers, and other youth-related organizations. Researchers can select the most suitable strategies based on their specific study design and requirements.