Sources for Top Charities page
Published: November 2020; Updated November 2021
Estimating the impact of your donations
For information about our general approach to estimating the impact of the charities and funding opportunities we recommend, see this page.
GiveWell has 22 full-time research staff. The names and roles of research staff can be found here.
Each research staff member contributes about 2,000 hours per year (46 weeks at 40 hours per week). We assume that one-quarter of their time is spent on non-research work, such as staff meetings. We thus roughly estimate that they collectively conduct more than 30,000 hours of research per year (22 staff multiplied by 2,000 hours per year multiplied by 75% of time on research).
Impact of malaria
Estimates of annual malaria deaths vary from about 410,000 to 640,000.1 At least 90% of the malaria deaths reported by the World Health Organization (WHO) for 2019 were in sub-Saharan Africa, and children under five years old accounted for about two-thirds of malaria deaths globally.2
Presuming the proportion of children dying from malaria is approximately constant across countries, then about 60% of total malaria deaths were children under 5 years old in sub-Saharan Africa (90% of total malaria deaths in sub-Saharan Africa multiplied by 67% of total malaria deaths occurring in children under five).
Impact of vitamin A deficiency
The Institute for Health Metrics and Evaluation's Global Burden of Disease project estimates that vitamin A deficiency increases the risk of diarrhea, measles, and lower respiratory tract infections.3 In 2017, an estimated 233,000 global deaths were linked to this increased risk.4
Impact of vaccine-preventable diseases
Impact of parasitic worms
Many types of parasitic worms infect human beings, causing illnesses including schistosomiasis and soil-transmitted helminthiasis. Hundreds of millions of people have these infections.7
According to Our World in Data’s analysis of the World Bank’s PovcalNet data, about 62% of the world’s population in 2017 had per capita consumption of $10 per day or less ($3,650 per year or less).8
The Global Burden of Disease (GBD) project estimates more than 640,000 global deaths from malaria in 2019. “Measure: Deaths, 2019 number: 643,380.9.” Institute for Health Metrics and Evaluation, Global Burden of Disease, GBD Compare, Global malaria deaths. The World Health Organization (WHO) estimates approximately 409,000 malaria deaths in 2019. “Globally, malaria deaths have reduced steadily over the period 2000–2019, from 736 000 in 2000 to 409 000 in 2019.” WHO, World Malaria Report 2020, Pg xv.
WHO, World Malaria Report 2020, Pg 21, Figure 3.2d. For the list of countries in sub-Saharan Africa, see United Nations Development Programme, "About sub-Saharan Africa". “The percentage of total malaria deaths among children aged under 5 years was 84% in 2000 and 67% in 2019.” WHO, World Malaria Report 2020, Pg xv.
"In its Global Burden of Disease (GBD), IHME models VAD [vitamin A deficiency] as both a direct cause of years lived with disability (YLDs) and as a risk factor for three other diseases (diarrheal diseases, lower respiratory tract infections (LRTIs), and measles)." GiveWell's non-verbatim summary of a conversation with the Institute for Health Metrics and Evaluation, April 5, 2019
The GBD project attributes 233,000 deaths to "Vitamin A deficiency: all causes" in 2017. GBD 2017 Risk Factor Collaborators, 2018, p. 1948.
"In 2019, global coverage rates for the third dose of the diphtheria, tetanus and pertussis vaccine (DTP3) reached 85 per cent." This vaccine is "often used as an indicator of how well countries are providing routine immunization services." UNICEF, "Immunization," 2020. We say “at least” because coverage tends to be lower for other vaccines. For global vaccination rates, see Our World in Data, Global vaccination coverage, World, 2019.
In 2019, 57% of infants in Nigeria received the third dose of the diphtheria, tetanus, and pertussis vaccine. Our World in Data, Global vaccination coverage, Nigeria, 2019
According to the Global Burden of Disease (GBD), global prevalence of cases of intestinal worms in 2019 is as follows: schistosomiasis, 140.0 million; hookworm disease, 172.5 million; trichuriasis, 360.3 million; and ascariasis, 445.6 million. @Institute for Health Metrics and Evaluation, Global Burden of Disease, GBD Results Tool, Global parasitic worm infection prevalence@.
“37.65% above $10/day, 2017.” Rosen and Ortiz-Ospina, 2019, Distribution of population between different poverty thresholds, World, 1981 to 2017.