Background: Recruitment and retention of minority racial/ethnic groups is necessary to assess and address cancer health disparities in the United States. The objective of this study was to characterize participants’ retention status and identify baseline participant factors associated with retention among an entirely African American (AA) population in a randomized controlled trial (RCT).
Methods: Using data from the Healthy Eating and Living in the Spirit (HEALS) program, an RCT conducted from 2009 to 2012 among AAs in South Carolina we examined participant-level factors associated with retention. We used SAS v9.4 to compute chi square tests and fit logistic regressions in order to compare 220 (53.14%) retained to 194 not-retained participants with the goal of identifying important predictors of retention. Among the entire study population, main predictor variable of interest was network distance in miles from home of participants to the clinic venue (i.e. their church) whereas among participants randomized to the intervention arm, a second predictor was percentage of intervention classes attended.
Results: Baseline characteristics that were significantly associated with retention status included group assignment, age, body mass index (BMI), distance from home to clinic site(s), and partner enrollment in the study. Participants who lived in locations >5 miles from the clinic sites were more likely to be retained in the study (OR = 1.58; 95% CI: 1.04 - 2.4) compared to participants who lived <5 miles away from the clinic. Older participants (>60 years) were 3.3 times as likely (95% CI: 1.59 - 6.81) than those aged < 41 years to be retained while individuals randomized to the control group were more likely to be retained (OR = 1.63; 95% CI: 1.06 - 2.50) compared with those randomized to the study group. Those who were obese were less likely to be retained (OR = 0.37; 95% CI: 0.17 - 0.79) compared to those who had normal BMI. Participants who had their partner enrolled in the study were less likely to be retained (OR = 0.59; 95% CI: 0.36-0.95) compared with participants who did not have their partners enrolled. Among individuals randomized to the intervention arm, attending 60% of the classes in the first 3 months of the RCT was strongly predictive of being retained in the study with an odds ratio of 4.31 (95% CI: 2.25 - 8.24) compared with those who did not complete 60% of the classes.
Conclusions: Participants who lived further away (>5 miles) and attending 60% or more of the intervention classes was strongly predictive of being retained in the study. Ensuring that there is a run-in period as part of the screening procedure for all participants before randomization will help project managers to identify participants that are likely to be retained in the study and more
studies need to be done to know why those who lived farther away were more likely to be retained.
Citation Format: Oluwole A. Babatunde, Swann A. Adams, Michael D. Wirth, Jan M. Eberth, Jameson Sofge, Brook Harmon, Lisa Davis, Ruby Drayton, Tom Hurley, Heather M. Brandt, James R. Hebert. Predictors of participants’ retention among African Americans in the Healthy Eating and Living in The Spirit (HEALS) trial. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1764.