The study was conducted in south-western Samburu County, Kenya between October 2017 and September 2018. Three survey rounds were completed. Interviews were conducted in-person at single village locations in each of five villages. Four tools were used in each interview: i) Raven's Progressive Matrices (standard adult, short-form), ii) complex span Working Memory Capacity task, iii) Discrete Choice Experiment, and iv) self-reported survey. All surveys were conducted in Samburu, with the aid of local enumerators.
Research design and associated tools
used in the study were approved by the Washington State University
Institutional Review Board (#16207) and the Kenyatta National
Hospital-University of Nairobi Ethics and Research Committee (P613-10/2017). Oral
consent was obtained from study participants.