Cost per Participant
We calculated costs per participant for the intervention including capital and recurring costs at the level of the intervention, counselor and participant, by combining all related costs per booster delivery type (live call, SMS, IVR) over the analysis period. These were then divided by the number of participants who received each booster session delivery type, including those receiving the intervention in the wait-list control arm, to produce per-participant costs for each booster delivery type. We separated per-participant costs into start up and implementation costs.