[1] This framing doesn't apply to every program. For a program like unconditional cash transfers, in which selected families living in poverty receive cash without a requirement to meet additional conditions, it might make sense to focus primarily on the cost per household and the effect on each household. But for many of the programs we look at, like health programs that aim to cover an entire population in which not everyone is affected by a particular problem, the burden of the problem the program addresses is an important factor.
[2] We last updated our full report on insecticide resistance in 2020, and have continued to research it. This spreadsheet has our current bottom-line estimates of insecticide resistance by country and type of net.
[3] In the case of our April 2023 grant to Helen Keller International for vitamin A supplementation in Madagascar, we noted, "a recent survey estimated that 44% of children have been receiving VAS in the areas Helen Keller plans to support. We may over- or under-estimate cost-effectiveness if either (a) Helen Keller's support primarily leads to reaching children who would [not] have received VAS without their support, or (b) the additional children reached are systematically at lower [higher] risk of illness and death than those who are reached by the routine health system."
[4] In many of our cost-effectiveness analyses, we consider what other funders are contributing and how our funding might change their actions, as discussed in this 2018 blog post. (Note that the specific numbers in the 2018 blog post are now outdated.)
[5] For our grant to Evidence Action for syphilis screening and treatment in pregnancy in Zambia and Cameroon, we created forecasts, including projecting a 55% chance that "Evidence Action will have fully transitioned this work to the government in Zambia in 5 years (2027), spending less than $150,000 per year in-country on this program." We also projected a 50% chance that the Zambian government would have scaled up the program in one year in the absence of Evidence Action's support (see this section of our cost-effectiveness analysis).
[6] We estimate that New Incentives' program is 25% more cost-effective than our main model would otherwise suggest because of the benefits of herd immunity (see here). We don't actually model the disease transmission effects and think it would be challenging to do so, but we include the 25% increase in cost-effectiveness as a very speculative best guess of the magnitude of the effect.
[7] We compare different outcomes to one another via our moral weights. We currently value an averted death as roughly 100 times more valuable than a year of doubled consumption. These tradeoffs aren't limited to deaths averted vs. income increased; we also consider the value of disability averted (as in the case of clubfoot treatment) and other benefits.