Climate-smart agriculture adoption as a pathway to food security among smallholder farmers: a review paper

Introduction Climate-Smart Agriculture (CSA) is crucial for addressing food insecurity, climate change, and rural poverty in developing countries. It is predominantly adopted by smallholder farmers who rely on rain-fed agriculture and are highly vulnerable to climate variability. This systematic review aims to identify empirical gaps in smallholder farmers' adoption of CSA practices and examine their implications for achieving food security. Methods Guided by PRISMA standards, the review included empirical, peer-reviewed studies that clearly articulated dependent variables, research designs, theoretical frameworks, and inferential statistical methods. A total of 58 studies published between 2016 and 2025 were analyzed. These studies covered 18 countries and 5 multi-country contexts across Sub-Saharan Africa (78%, n = 45) and South Asia (22%, n = 13). Results The findings indicate that food security (43%, n = 25) was the most frequently examined outcome, followed by CSA adoption (24%, n = 14), household income (19%, n = 11), and crop production (14%, n = 8). The CSA Framework was the most commonly applied theoretical approach ( n = 8), followed by Diffusion of Innovation Theory ( n = 4), although many studies lacked explicit theoretical grounding. Methodologically, cross-sectional surveys and econometric models dominated, offering strong quantitative evidence but limiting insights into temporal, systemic, and contextual dynamics. The limited integration of qualitative approaches constrained understanding of the complex and location-specific nature of CSA adoption and its impacts. Geographically, the evidence was unevenly distributed, with Ethiopia ( n = 11), India ( n = 8), and Ghana and Nigeria ( n = 5 each) most represented, while other countries were underrepresented. Smallholder farmers were the primary study population ( n = 32), and access to extension services emerged as the most frequently examined independent variable ( n = 13). Discussion The review highlights significant theoretical, methodological, and geographical gaps in CSA research. To address these gaps, governments and development partners should co-design context-specific CSA programs with smallholder farmers. Strengthening extension services through participatory training that integrates indigenous and scientific knowledge is essential.