Hi, reasons for reassuring children, young people and adults of the confidentiality of shared information are trust, safety and law.
Children, young people and adults need to know confidentiality will be honoured unless their, or other's safety and well-being is threatened, a crime has or is likely to be committed, and a professional's knowledge of and access to the child, young person or adult's information will not be abused, in the same way that it is important for professional's to understand how important shared information is, where and how it's stored, transported and disclosed to other appropriate professionals.
Safety & safeguarding
Data Protection act 1998
Freedom of information act 2000 ensures an individual has the right to access information that is about them.
Article 8 of the Human rights act highlights privacy as a right as does
article 16 of the UNCRC
Hth
Level 3 handbook search