The following two changes to the diagram are needed:

A CellPhone communicates with a Physician via Messages. A Message contains the attributes of dateTime and text. A CellPhone can send one or more Messages or no Messages at all. A message comes from one and only one CellPhone. A Message is sent to one and only one Physician. A Physician can receive one or more Messages or no Messages at all.

A GlucoseObservation triggers an Alert. An Alert contains the attributes of dateTime and urgentLevel. A GlucoseObservation can send one or more Alerts or no Alerts at all. An Alert comes from one and only one GlucoseObservation. An Alert is sent to one or more than one Physician. A Physician can receive one or more Alerts or no Alerts at all.