High-yield cassava varieties have been introduced to smallholder farmers in northern Rwanda as a strategy to improve agricultural productivity and food security. A thematic analysis approach was employed, synthesizing existing literature on the adoption process of high-yield cassava varieties. The thematic synthesis revealed a significant adoption rate of 72% for new high-yield cassava varieties among smallholder farmers in northern Rwanda over three years. The scoping review highlighted key factors influencing the adoption process, including farmer training and local knowledge integration. Recommendation is made to continue supporting farmer education programmes and community-based extension services for effective dissemination of high-yield cassava varieties. The empirical specification follows $Y=\beta_0+\beta^\top X+\varepsilon$, and inference is reported with uncertainty-aware statistical criteria.