The link between somatic conditions and challenging behaviour

It seems clear that there is a link between somatic conditions and challenging behaviour. However, people often fail to see that challenging behaviour can be caused by somatic conditions for a number of different reasons.

The diagram below shows how this works.
 

Somatic condition [...]

Symptoms

Visible symptoms (apparent to others) [...]
Hidden symptoms (only apparent to client) [...]
 

Expression of complaints [...]

The client can express complaints effectively
The client cannot express complaints effectively [...]
 

Observation by others

Symptoms are observed by others
Complaint is heard/noted by others
Symptoms are not observed by others [...]
Complaint is not heard/noted by others [...]
 

Others respond

Adequately (medical assistance)
Inadequately (no medical assistance) [...]
 
Risk of challenging behaviour