Effectiveness of recruitment strategies to increase diversity within one trial site in a post-partum weight management intervention: the Supporting MumS Randomised Controlled Trial 

Problem

Under-served groups in society have, historically, been excluded from participating in clinical trials (NIHR, 2020). There is currently no systematic approach to address the lack of representation in clinical trials (Witham et al., 2020). Inclusion is paramount to redress inequitable health disparities, prevent further widening of inequalities, and accurately evaluate the safety of new medicines and interventions. Thus this study aimed to explore the recruitment strategies used at one site participating in the UK-wide Supporting MumS (SMS) randomised controlled trial in relation to sample diversity.

Approach

The Supporting MumS trial is a UK-wide, multi-centre RCT that aims to examine the effectiveness of an automated text message intervention to support weight management in the postpartum period. London was chosen as one of five trial sites owing to its access to a diverse range of ethnic groups. Recruitment approaches included social media advertisement (Facebook/Instagram ads), GP surgeries and community-based approaches. For community-based recruitment, the researchers in London (AI and EOA) attended a range of council-run mum and baby groups (n=19). Six GP surgeries conducted patient database searches and sent text messages to 321 women who matched the study inclusion criteria. Finally, paid Facebook/Instagram ads were targeted to relevant users within a 9km radius of Sydenham district over 2.5 months. Participant ethnicity, indicators of socio-economic status (household income and education), and details of how participants were recruited and the recruiting researcher, were extracted from the London site trial database. Data on the sample recruited are described using descriptive statistics and a chi-squared test was used to examine if there were any differences in the sample characteristics recruited by the two London researchers, who were from different ethnic groups.

Findings

The London recruitment target of 189 women was met over a seven-month period. The vast majority of participants, 94%, were recruited through community-based, face-to-face methods (n=177), with another 4% (n=8) through GP surgeries, and 2% (n=4) via social media advertisement. 44% (n=84) of the sample was Black, Black British, Caribbean or African, 28% (n=53) was White, 11% (n=21) was Asian or Asian British, 10% (n=19) was Mixed or Multiple Ethnic groups, and 6% (n=6) was Other Ethnic Group. Based on a chi-square test there was no evidence that researcher ethnicity was associated with the profile of recruited participants in terms of ethnicity (p=0.810), level of education (p=0.215), or household income (p=0.448).

Consequences

An ethnically diverse sample of women was recruited in London using targeted recruitment strategies. Of the methods used, in-person meetings in community settings were the most successful avenue of recruitment, perhaps by helping to build a sense of trust. Retention of women from different backgrounds will be examined in the UK-wide SMS trial.