Fig. 4

Incremental cost effectiveness ratio (ICER) values and 95% uncertainty intervals (UI) for the base case (top bar) and scenario analyses (following two bars). The middle bar represents scenario (A): replacing the 1-day training session for in-school-champions with a no-cost online educational session and maintaining 60% of the original treatment effect (‘best case’ scale-up penalty). The bottom bar represents scenario (B): replacing the 1-day in-school champion training session with a no-cost online educational session and maintaining 25% of the original treatment effect (‘worst case’ scale-up penalty)