Background
Implementation of evidence-based interventions often involves strategies to engage diverse populations while also attempting to maintain external validity. When using health IT tools to deliver patient-centered health messages, systems-level requirements are often at odds with 'on-the ground' tailoring approaches for patient-centered care or ensuring equity among linguistically diverse populations.Methods
We conducted a fidelity and acceptability-focused evaluation of the STAR MAMA Program, a 5-month bilingual (English and Spanish) intervention for reducing diabetes risk factors among 181 post-partum women with recent gestational diabetes. The study's purpose was to explore fidelity to pre-determined 'core' (e.g. systems integration) and 'modifiable' equity components (e.g. health coaching responsiveness, and variation by language) using an adapted implementation fidelity framework. Participant-level surveys, systems-level databases of message delivery, call completion, and coaching notes were included.Results
96.6% of participants are Latina and 80.9% were born outside the US. Among those receiving the STAR MAMA intervention; 55 received the calls in Spanish (61%) and 35 English (39%). 90% (n = 81) completed ≥ one week. Initially, systems errors were common, and increased triggers for health coach call-backs. Although Spanish speakers had more triggers over the intervention period, the difference was not statistically significant. Of the calls triggering a health coach follow-up, attempts were made for 85.4% (n = 152) of the English call triggers and for 80.0% (n = 279) of the Spanish call triggers (NS). Of attempted calls, health coaching calls were complete for 55.6% (n = 85) of English-language call triggers and for 56.6% of Spanish-language call triggers (NS). Some differences in acceptability were noted by language, with Spanish-speakers reporting higher satisfaction with prevention content (p = < 0.01) and English-speakers reporting health coaches were less considerate of their time (p = 0.03).Conclusions
By exploring fidelity by language-specific factors, we identified important differences in some but not all equity indicators, with early systems errors quicky remedied and high overall engagement and acceptability. Practice implications include: (1) establishing criteria for languge-equity in interventions, (2) planning for systems level errors so as to reduce their impact between language groups and over time; and (3) examining the impact of engagement with language-concordant interventions on outcomes, including acceptability. Trial Registration National Clinical Trials registration number: CT02240420 Registered September 15, 2014. ClinicalTrials.gov.