Awareness and understanding of Optima.

Familiarity with mathematical modelling.

Findings corroborated global guidance.

Modelling contextualises global literature and evidence.

Extended training.

Local capacity.

Alignment with country targets and priorities.

Data availability and quality.

Scepticism of modelling.

Uncertainty in underlying data.

Dissatisfaction with choice or handling of data.

Results challenged expectations or beliefs.

Consequences for health and social equity.

Wide range of stakeholders.

Multisectoral engagement.

Key international funding organisations consulted throughout modelling process.

Local ownership.

Joint planning.

Opportunities for dialogue.

Interactive process.

Alignment with country needs and priorities.

Previous involvement.

Follow-up

Tailored and clear dissemination products.

Engagement with policy and programme leads.

Optima involvement driven by international funding organisations.

Insufficient opportunity for feedback.

Narrow participation.

Inadequate dissemination.

Completed prior to key grant applications.

Sufficient time allocated.

Data availability at time of analysis.

Integration with other modelling and costing exercises.

Finalised too late to inform key strategy or funding organisation decisions.

Other priorities competing for time and resources.

Health system reform.

Mechanisms to transfer funds between activities and funding streams.

Influence on budgeting decisions.

Funder preferences and priorities.

Historical allocation patterns.

Line-item budget systems.

Fragmented funding streams

Political will.

Sociopolitical unrest.

COVID-19 pandemic and response.