Produce an ERD and RDM corresponding to the following problem description.
The doctor in a small country town describes the situation, as it will be after the new computer system
is in use
Patients make appointments, these are recorded (in the computer system).
At the appointed time the patient arrives at the surgery and describes their symptoms, these are
matched against a list of standard symptoms and the severity of each symptom is recorded.
Some examples of standard symptoms are:
Nausea and chest pains after physical exercise
If this is the patient’s first visit their name, date of birth, sex and address are recorded.
If necessary a Course of Treatment is initiated for the patient, this can involve zero, one or more
Patient dosages are recorded for drugs etc, but not for ointments etc.
For example, a patient with a rash might be put on a Course of Treatment called ‘B Vitamin Therapy’,
where various doses of vitamins B1, B2, .
.., B6 are tried.
If this Course of Treatment fails, another
might be tried, such as ‘Heat Treatment’.
There is no standard (or fixed) name given to a Course of Treatment, rather, for each occasion the
doctor invents a suitable description/title.
The period of time over which a patient undertakes each Course of Treatment is recorded, as are the
relevant periods for the use of medications.
For each “generic” medication (as distinct from a “brand name” medication) the database contains a
“note” field and a list of possible side-effects.
The side-effects are identified with the standard
symptoms and their average frequency and severity is already recorded in the database.
many medications can produce Head Aches as a side effect.
For each generic medication a list of brand name medications is kept together with the manufacturer’s
name, address and phone number.
(All brand name medications classed under one generic medication
are identical in terms of their effects).
The information recorded about patients’ use of medications relates to generic medications, not brand
name medications. For continuing patients it may be necessary to adjust dosages and add or drop
medications from the Course of Treatment.
A patient could be under several Courses of Treatment at once, if they are suffering from several
If a symptom disappears permanently or for a substantial period, this is recorded.
Also the patient may
indicate a specific date when the symptom started.
Patients’ medical histories are retained permanently by the system, as are their appointments.
However, only their most recent name and address is kept.