Background: Malaria remains a major global threat despite the availability of efficacious tools. Its effective control requires consistent action from both health care systems and community and an understanding of features that precipitate risk. The Viet Nam National Malaria Control Programme (NMCP) introduced in 1991 has controlled malaria through the provision of free anti-malarial drugs, impregnated bed-nets, bi-annual home insecticide spraying and early diagnosis and treatment. Overall, the number of clinical cases declined from 1.2 million and 4646 recorded deaths in 1991 to 185 529 clinical cases and 50 deaths in 2002. However, over 90% of severe cases and deaths occurred in mountainous, forested and largely ethnic minority areas of central Viet Nam, where populations are impoverished, poorly educated, culturally and linguistically distinct and living in dispersed, less accessible settlements. The researchers therefore considered it both instructive and timely to investigate persistent malaria in such settings.

Methods: Mixed methods (qualitative and quantitative) were used to collect data, in order to explore the complex interrelations between the various actors and system elements. Data was collected in two stages. The formative stage used mainly qualitative tools (e.g. community meetings, observation of bed-net use, and focus group discussions/semi-structured interviews) while health managers, providers and the community helped to define and expand thematic areas of enquiry. Outcomes informed the quantitative approaches (e.g. a provider quiz, structured surveys with community members and village health workers, and quality check of microscopy facilities and health records at district and commune levels). The table describes the methods that were used.

Conclusion: Use of the mixed methods informed researchers and the NMCP about the contextual factors that acted as bottlenecks to effective malaria control in the affected region.

Lessons: The complexity of contextual factors coupled with poverty, low education levels, cross-border mobility, and cultural diversity, made it appropriate to use mixed methods.