Authors:
Robin E. Klabbers, Caryl Feldacker, Jacqueline Huwa, Christine Kiruthu-Kamamia, Agness Thawani, & Hannock Tweya
University of Washington affiliated authors are displayed in bold.
✪ Open Access
Published: Janurary 2025
Read the full text in the open access journal Implementation Science
Abstract:
Background
While key to interpreting findings and assessing generalizability, implementation fidelity is underreported in mobile health (mHealth) literature. We evaluated implementation fidelity of an opt-in, hybrid, two-way texting (2wT) intervention previously demonstrated to improve 12-month retention on antiretroviral therapy (ART) among people living with HIV (PLHIV) in a quasi-experimental study in Lilongwe, Malawi.
Methods
Short message service (SMS) data and ART refill visit records were used to evaluate adherence to 2wT content, frequency and duration through the lens of the Conceptual Framework for Implementation Fidelity. Message delivery and 2wT participant interactions were considered across four core 2wT components: 1) weekly motivational SMS messages; 2) proactive SMS appointment reminders; 3) SMS reminders after missed appointments; and 4) interactive messaging with 2wT staff about transfers and appointment rescheduling. Using mixed-effects logistic regression models adjusted for participant demographics, we examined the effect of core 2wT component fidelity on a) on-time appointment attendance and b) timely return to care after a missed appointment, presenting adjusted odds ratios (aORs) and 95% confidence intervals (CIs).
Results
The 468 2wT participants had a median of 52 study weeks (interquartile range [IQR] 34 – 52) with 6 ART appointments (IQR 4—7) of which 2 (IQR 1 – 3) were missed. On average, participants received a motivation message for 75% (IQR 56%—83%) of enrolled weeks, a reminder before 83% (IQR 67%—100%) of appointments, and after 67% (IQR 0%—100%) of missed appointments. Participants reported 9 transfers and rescheduled 46 appointments through 2wT prompts; 196 appointments were changed via unprompted interaction. Participants with 10% higher expected motivation message delivery were more likely to attend clinic appointments on time (aOR: 1.08; 95%CI: 1.01 – 1.16, p = 0.03). Receiving and responding to an appointment reminder in any way were also associated with increased on-time appointment attendance (aOR: 1.35; 95%CI: 1.03 – 1.79, p = 0.03 and aOR: 1.47, 95%CI: 1.16 – 1.87, p = 0.001, respectively). No associations were found for 2wT messages and timely return to care following a missed appointment.
Conclusion
Greater 2wT implementation fidelity was associated with improved care outcomes. Although implementation fidelity monitoring of mHealth interventions is complex, it should be integrated into study design.
Contributions to the literature
- Despite the recognized importance of implementation fidelity in digital health research, few studies evaluate and transparently report the extent to which mHealth interventions were implemented as intended.
- This study presents a framework-based evaluation of the implementation fidelity of a two-way texting intervention for HIV retention in a routine care setting in Malawi. Findings demonstrate how fidelity assessment not only facilitates replication of findings and generalizability assessment, but uncovers implementation challenges and generates hypotheses about intervention mechanisms of action.
- The benefits and complexity of implementation fidelity evaluation underscore the need to consider fidelity early and integrate monitoring mechanisms into study design.
**This abstract is posted with permission under the Creative Commons Attribution 4.0 International License**