Fig. 1

Schematic of decision tree model. A decision tree visually shows events and/or states of nature of different decisions or scenarios over a fixed time horizon. The grey square at the base of the tree is a decision node that shows the competing alternatives that a decision-maker is choosing between. Rectangles represent different events or states along the pathway of a decision; events from each divergence point in the tree are mutually exclusive and collectively exhaustive (e.g., “with malaria” and “without malaria”). Shaded squares represent additional branches in the tree that were omitted for simplicity. Each branch is associated with a probability. Some branches and states have been grouped, truncated, and represented by a coloured and labelled circle. CHW, community health worker. RDT, rapid diagnostic test