"Ordinarily we would expect the person to have shown the pattern of behaviour that presents such a challenge to services for a considerable period of time.
Increasingly professional groups are adopting alternative terms for example "behaviour of concern".
However, research evidence indicates that challenging behaviours and mental health problems are relatively independent conditions.
Children communicate through their behaviour, especially those who have not acquired language and vocabulary skills to tell the adult what the problem is.
In adults with developmental disabilities certain types of challenging behaviour can predict contact with police and hospital admission.