The purpose of the review is to investigate various relations between the concepts of competence and participation found within child and youth research with the aim of identifying differences in practical reasoning of the various kinds of child research. The search identified 260 articles, and an in-depth analysis of 39 articles was conducted, elaborating the conceptual differences inherent in the different child research fields. Based on a philosophy of practice, the analysis identified 3 different causal connections between the concepts of competence and participation, indicating 3 different ways of understanding means and ends in child research. The review thereby offers an understanding of how and why interdisciplinary problems sometimes occur in education and child care.