Effects of Recruitment Messaging on Ethnic/Racial Minority Screening in a RCT for Prenatal Insomnia: An Experimental Approach.

Objective: Using data from a nationwide recruitment campaign for an RCT evaluating digital cognitive behavioral therapy for prenatal insomnia, we tested whether a recruitment message that identified a racial/ethnic disparity in sleep quality (sleep disparities message) would increase the proportion of participants who engaged in study screening compared to a recruitment message without identified ethnic/racial disparities (standard message). We also tested whether the magnitude of the association of message type with completed eligibility screening varied by race/ethnicity.

Method: Pregnant people (n = 203,664) were randomly assigned to receive a sleep disparities or standard recruitment e-mail. A total of 1,782 pregnant people opened the recruitment e-mails. We used chi-square tests to compare the proportions of e-mails that led to study screening outcomes between the two e-mail message conditions.

Results: The chi-square tests revealed that a smaller proportion of prospective participants who received a sleep disparities message visited the screening website X² = 8.83, p = .003 and completed a study screener X² = 4.92, p = .026 compared to those who received a standard message. Results of a logistic regression detected no statistically significant interactions between race/ethnicity and message type on the probability of a completing a study screener.

Conclusion: Manipulating and measuring the effects of recruitment messages can identify effective strategies for diversifying the participant pools in CBT-I trials.