In 2007, the National Health and Medical Research Council (NHMRC) released a revised National statement on ethical conduct in human research. Public submissions in the review process leading to the 2007 statement highlighted four main areas of concern: children's competence to consent, mature minors and the requirement for parental consent, whether children can refuse to participate, and the provision of information to children. A useful addition to the statement is the concept of levels of maturity, which help determine whether a child or young person's consent is necessary and/or sufficient for participation in research. Changes in terminology ("capacity" instead of "competence" and introduction of the term "vulnerability") have the potential to create confusion, as the new terms are not clearly defined, and capacity is used in several senses.