Assessing drivers of implementing “Scaling-up the Systems Analysis and Improvement Approach” for Prevention of Mother-to-Child HIV Transmission in Mozambique (SAIA-SCALE) over implementation waves

BACKGROUND: The Systems Analysis and Improvement Approach (SAIA) is an evidence-based package of systems engineering tools originally designed to improve patient flow through the prevention of Mother-to-Child transmission of HIV (PMTCT) cascade. SAIA is a potentially scalable model for maximizing the benefits of universal antiretroviral therapy (ART) for mothers and their babies. SAIA-SCALE was a stepped wedge trial implemented in Manica Province, Mozambique, to evaluate SAIA’s effectiveness when led by district health managers, rather than by study nurses. We present the results of a qualitative assessment of implementation determinants of the SAIA-SCALE strategy during two intensive and one maintenance phases. METHODS: We used an extended case study design that embedded the Consolidated Framework for Implementation Research (CFIR) to guide data collection, analysis, and interpretation. From March 2019 to April 2020, we conducted in-depth individual interviews (IDIs) and focus group discussions (FGDs) with district managers, health facility maternal and child health (MCH) managers, and frontline nurses at 21 health facilities and seven districts of Manica Province (Chimoio, Báruè, Gondola, Macate, Manica, Sussundenga, and Vanduzi). RESULTS: We included 85 participants: 50 through IDIs and 35 from three FGDs. Most study participants were women (98%), frontline nurses (49.4%), and MCH health facility managers (32.5%). An identified facilitator of successful intervention implementation (regardless of intervention phase) was related to SAIA’s compatibility with organizational structures, processes, and priorities of Mozambique’s health system at the district and health facility levels. Identified barriers to successful implementation included (a) inadequate health facility and road infrastructure preventing mothers from accessing MCH/PMTCT services at study health facilities and preventing nurses from dedicating time to improving service provision, and (b) challenges in managing intervention funds. CONCLUSIONS: The SAIA-SCALE qualitative evaluation suggests that the scalability of SAIA for PMTCT is enhanced by its fit within organizational structures, processes, and priorities at the primary level of healthcare delivery and health system management in Mozambique. Barriers to implementation that impact the scalability of SAIA include district-level financial management capabilities and lack of infrastructure at the health facility level. SAIA cannot be successfully scaled up to adequately address PMTCT needs without leveraging central-level resources and priorities. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03425136. Registered on 02/06/2018. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s43058-023-00422-6.