Testing procedure

We obtained ethical approval from The Ethical Review Board of Jimma University, Ethiopia (RPGC/36/2013, dated 13/02/2013). We also obtained written informed consents from the children’s parents. Measurements and testing were performed by four trained nurses, who spoke both Afan Oromo and Amharic languages. They were trained for 1 month by a child development expert and a nutritionist on the theoretical and practical aspects of overall child development, care, nutrition, anthropometric methods, Denver II-Jimma, the structured questionnaire and ASQ: SE. To reduce possible biases, the testers were blinded; they did not know to which group a child belonged. The testers assessed children in both groups and the assessments were performed at the children’s homes while their caregivers were present. Prior to testing, the tester created a relaxing environment with the child and its respective caregiver. Regarding the assessment order, a questionnaire, together with ASQ: SE, was administered first; the Denver II-Jimma next and finally, the anthropometric measurements. The assessment time for a child took about an hour.