Developmental dyscalculia can be divided into difficulties with number sense, number facts, computation, and mathematical reasoning. The relationship between number sense performance and other performance has been reported in other countries, but the relationship has not been examined at younger ages. Furthermore the way of perceiving numbers differs from culture to culture, and these relationships have not been confirmed in Japan. Therefore, we collected basic data on the relationship between number sense and mathematical facts, computation, and mathematical reasoning, and aimed to clarify the relationship between the two. We administered tasks on number sense (ordinal and cardinal), number facts, computation, and mathematical reasoning (4th grade only) to 188 4th graders, 371 1st graders, and 330 2nd graders in regular classes in public elementary schools enrolled. The results revealed that number sense cardinality explains the significant relationship of some impairments in number facts and computation. The results of the present study were considered to replicate the results of previous studies in which number sense was significantly associated with explaining numerical facts, computation, and mathematical reasoning, and to show that this relationship was common across ages.

Trauma-Informed Care (TIC) is a system that provides trauma support, taking into account trauma that the user has experienced and its impact, as well aiming to prevent re-traumatization. In pediatric medicine, there are many cases related to trauma, and thus, even though there is a desire for TIC’s widespread use, there are still few in pediatric medicine endeavoring to implement it. In order to comprehend the recognition of TIC, its understanding and spread within pediatric medicine, and further to consider possible responses needed in the future, we conducted a questionnaire survey of pediatric hospitals nationwide. Although the concept of TIC was only just beginning to be known, we received many responses indicating that TIC-based initiatives had actually been put into practice with patients and among medical staff, and that they had experienced the benefits of doing so. Further, it was thought that in the future, as more people involved in pediatric healthcare deepen their understanding of TIC, support will be able to be provided that lessens trauma for users and healthcare workers, including support that recognises trauma symptoms. And thusly that pediatric healthcare will become a more secure and safe environment.