University of Washington — Deworming Follow-up Planning Grant (March 2022)

Published: April 2022

In March 2022, GiveWell recommended that Founders Pledge grant $111,856 to the University of Washington. The funding will support Judd Walson, DeWorm3 study Principal Investigator, and Sitara Ajjampur, DeWorm3 India Site Principal Investigator. The grant will support the research team's time over nine months to develop a plan for following up with the study participants to track medium- or long-term impact. The project is described in this concept note and budget. The expected output of the project is a research protocol for biological outcomes and cognitive development a few years after the start of the trial, with estimates of statistical power and cost.1 It is possible that we'd later extend the study to measure economic outcomes once participating children have reached adulthood.

The case for the grant is:

  • It is possible that the existing randomization of the DeWorm3 study could allow for a further data collection that would update the evidence for the long-term impact of deworming.2 GiveWell makes or recommends grants totaling tens of millions of dollars to deworming programs every year,3 and these grants are largely based on a single study.4 An additional study has the potential to update our views and grantmaking a lot.
  • There is an existing team organized around the DeWorm3 study,5 and additional research could leverage that infrastructure and knowledge. The DeWorm3 study was funded by a large grant from the Bill & Melinda Gates Foundation that included over 360,000 individuals in Benin, India and Malawi.6
  • This is an opportunity to leverage the money and time already invested in the DeWorm3 randomized controlled trial (RCT), which would reduce the cost and time-to-results of a follow-up study.
  • A planning grant is a small investment that will hopefully allow us to answer key questions, particularly on outcome measures and statistical power, before committing large amounts of time and money into further research.


  • We think it's fairly unlikely that we will fund further research, based on a guess that it will not be feasible to get enough statistical power to make the research worthwhile. This guess is based on some rough calculations we did of the conditions under which we would expect to be able to measure a statistically significant impact of childhood deworming on adult income. Even so, we think it is worth answering the question of statistical power more formally through this planning grant, in case our initial impressions are wrong.
  • A follow-up study is only possible if the primary DeWorm3 study successfully reduced worm burden in treatment areas. Results on this outcome are not yet available.
  • Given the relatively small size of this grant, we have not subjected this grant to the level of internal review that we would for a larger grant. A Program Officer and a Senior Researcher had conversations with the principal investigators and did a light review of the concept note.

This grant was investigated at a relatively shallow level.


Document Source
DeWorm3, Home page Source (archive)
DeWorm3, "Study Progress" Source (archive)
DeWorm3, "Who We Are" Source
GiveWell, "Combination Deworming," 2018 Source
GiveWell, "GiveWell’s money moved in 2020," 2021 Source
Judd Walson, email to GiveWell, February 23, 2022 (unpublished) Unpublished
Judd Walson, email to GiveWell, March 2, 2022 (unpublished) Unpublished
Miguel and Kremer 2004 Source
Walson, "Proposal: Initial planning grant," 2022 Source
Walson, Planning grant budget, 2022 (redacted) Source
  • 1
    • "We propose a planning grant to develop a protocol to assess the long-term impact of deworming on household consumption and assets, as well as key health indicators that may be important determinants in the pathway between helminth infection and economic outcomes." Walson, "Proposal: Initial planning grant," 2022, p. 2.
    • "For the planning grant, we propose the following: Initial background research to finalize study outcomes and optimize inputs into power calculations from existing data, including data from DeWorm3." Walson, "Proposal: Initial planning grant," 2022, p. 3.
    • Judd Walson, email to GiveWell, February 23, 2022 (unpublished); Judd Walson, email to GiveWell, March 2, 2022 (unpublished).

  • 2

    "We believe that it may be possible to utilize the randomization within the DeWorm3 clusters to assess outcomes based on the time individuals are exposed to infection. By leveraging the cluster randomized design, coupled with the inclusion of neighboring communities not treated by the trial, we may be able to design a highly efficient trial to assess these outcomes." Walson, "Proposal: Initial planning grant," 2022, p. 2.

  • 3

    For example, in 2020 a total of $15.7 million was directed to deworming campaigns (see this blog post). In 2021, $39.8 million was directed to deworming campaigns, and we project at least that amount in 2022 (based on unpublished internal records).

  • 4

    The primary study is Miguel and Kremer 2004. See further discussion of the evidence base for deworming here.

  • 5

    For information about the team working on DeWorm3, see this page.

  • 6

    For information about the progress of DeWorm3, see this page.