Solar-Powered Mobile Clinics for Improving Maternal and Child Health: A Systematic Review

Background and Rationale Maternal and child health (MCH) services in many low- and middle-income countries (LMICs) remain limited due to poor infrastructure, unreliable energy supply, and inadequate access to skilled health professionals. Conventional mobile health clinics, often diesel-powered, face operational and sustainability challenges. Solar-powered mobile clinics (SPMCs) have emerged as an innovation to address these challenges. They integrate renewable energy into mobile service delivery, allowing extended operational hours, reliable vaccine cold chains, diagnostic support, and reduced carbon emissions. Although individual studies and pilot projects have been reported, evidence was fragmented. Therefore, a systematic review was conducted to synthesise global evidence on SPMCs in relation to their design, implementation, health outcomes, barriers, and sustainability. 2. Objectives The review was guided by four research questions: What models of SPMCs have been implemented globally, and how do they differ in design and function? What effects do SPMCs have on maternal and child health outcomes (e.g., antenatal care, skilled birth attendance, immunisation, neonatal survival)? What barriers and enablers influence their implementation, sustainability, and scalability? How do SPMCs integrate with digital health technologies and health systems? 3. Eligibility Criteria Inclusion Criteria Population: Women of reproductive age, pregnant women, neonates, and children <5 years. Interventions: Solar-powered or hybrid mobile clinics delivering MCH services. Comparators: Conventional diesel-powered units, fixed facilities, or no intervention. Outcomes: Maternal and child health outcomes (ANC, SBA, mortality, immunisation), operational metrics (uptime, autonomy, CO₂ reduction), cost/sustainability, policy or community engagement. Study Designs: Quantitative, qualitative, mixed methods, and systematic reviews. Time Frame: January 2010 – March 2024. Language: English. Exclusion Criteria Commentaries, conference abstracts, editorials. Mobile health/e-health interventions without a physical clinic. Studies without empirical outcomes or without an MCH focus. 4. Information Sources Databases searched: PubMed (MEDLINE), Scopus, Web of Science Core Collection, WHO Global Health Library. Other sources: Reference lists and grey literature (WHO, UNICEF, World Bank). Final search date: March 31, 2024. 5. Search Strategy An example PubMed search string: ("solar-powered" OR "solar energy" OR "photovoltaic system*" OR "renewable energy") AND ("mobile clinic*" OR "mobile health unit*" OR "outreach health service*") AND ("maternal health" OR "maternal mortality" OR "antenatal care" OR "child health" OR "neonatal survival" OR immuni* OR "skilled birth attendance") Adaptations were applied for Scopus, Web of Science, and WHO Global Health Library. 6. Study Selection Records were imported into Zotero for deduplication. Two reviewers independently screened titles and abstracts; disagreements were resolved by a third reviewer. Full texts were retrieved for potentially relevant studies and assessed against eligibility criteria. The process was documented using the PRISMA 2020 flow diagram. 7. Data Extraction A standardised form captured: Bibliographic details (author, year, country, setting). Intervention features (solar configuration, autonomy, service type). Outcomes (MCH indicators, operational and environmental metrics). Implementation context (community engagement, policy, cost). Study design and methods. Two reviewers extracted data independently and cross-checked entries. 8. Risk of Bias Assessment Quantitative studies: Cochrane Risk of Bias (RoB 2.0). Qualitative studies: CASP checklists. Mixed-methods studies: MMAT tool. Systematic reviews: AMSTAR-2. Discrepancies were resolved by consensus. 9. Data Synthesis Due to heterogeneity, no meta-analysis was conducted. Findings were synthesised narratively. Quantitative outcomes: Summarised descriptively (e.g., ranges, medians, percentage change). Qualitative outcomes: Thematic synthesis of barriers, enablers, and policy factors. Subgroup analyses were conducted by region, intervention type, and study design. 10. Outcomes of Interest Maternal: ANC coverage, skilled birth attendance, maternal mortality. Child: Immunisation coverage, neonatal/child mortality, nutrition outcomes. Operational: Uptime, autonomy, service hours, PV efficiency, CO₂ avoided. Economic: Cost-effectiveness compared with diesel units. Implementation: Community acceptance, training needs, policy support. 11. Ethics and Dissemination Ethical approval was not required (secondary analysis of published data). Findings have been submitted as a peer-reviewed manuscript. Supplementary materials are being archived in Zenodo under CC-BY 4.0 license. 12. Registration The completed protocol and datasets was archived in Zenodo with DOI. .