Background: Process evaluations of randomized controlled trials (RCTs) can provide insight and inform us on the intervention implementation, causal mechanisms and the contextual factors; whether an intervention is effective or ineffective due to implementation failure or failure of the intervention itself. Hence, we aim to consolidate the methodology from previous process evaluations of complex interventions in healthcare services upon their findings on facilitators and barriers to address the prevention of type 2 diabetes among women with gestational diabetes mellitus (GDM).
Methods: Comprehensive search will be conducted on electronic databases, trial registers, and reference lists of recent reviews for RCTs of complex interventions which address process evaluations of diabetes prevention intervention (DPI) for women with GDM in healthcare settings. There are no restriction on the year of publication and language of the papers. Data from each study will be extracted by two reviewers independently using standardized forms. Data extracted include descriptive items on the study design and the outcomes of process evaluations from the three dimensions: (1) implementation (theoretical framework, reach, dose delivered, dose received, fidelity, behaviour change techniques and competency in delivering them); (2) mechanistic (format of delivery either digital, non-digital or hybrid, participant and healthcare provider experience and feedback; (3) contextual (socio-cultural context, the organisational factors, local and national policy factors as barriers, facilitators, contamination and adoption for the DPI and the control as well as the conflict of interest). The quality of the studies will be assessed using mixed methods appraisal tool (MMAT) which designed for the appraisal stage of systematic mixed studies reviews. A narrative and thematic synthesis of the findings will be presented to inform the contents of a new DPI for women with GDM.
Discussion: The findings from this process evaluation findings are valuable in determining whether a complex intervention should be scaled up or modified for other contexts in future plan. Publishing this protocol could benefit our understanding on how the process evaluation have been conducted thus far and give deeper input in understanding potential challenges and solutions to aid in the implementation of effective DPIs for GDM in Malaysia.
Systematic Review Registration: CRD42020208212