This paper describes an experiment to determine which personality characteristics can be used to predict whether a child will make an effective participant in a user test, both in terms of the number of identified problems and the percentage of verbalised problems. Participant selection based on this knowledge can make user testing with young children more effective. The study shows that the personality characteristic Curiosity influences the number of identified problems; a combination of the personality characteristics Friendliness and Extraversion influences the percentage of verbalised problems. Furthermore, the study shows that selection of children based on these criteria does not lead to finding an unrepresentative sample of the product's problems.
Barendregt, W., Bekker, M. M., Bouwhuis, D. G., & Baauw, E. (2007). Predicting effectiveness of children participants in user testing based on personality characteristics. Behaviour & Information Technology, 26(2), 133-147. https://doi.org/10.1080/01449290500330372