Use Case Example
Usage Narrative -- An Example
• Suppose you’ve been asked to work as a business or
systems analyst on a new system to track pharmacy
functions in a hospital.
• You decide a good first step might be to construct a
usage narrative to begin the analysis process.
• On the next slide is an example of what you might
produce.
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Example Usage Narrative -- Hospital Pharmacy
The Hospital Pharmacy fills prescriptions for the hospital’s patients and distributes these to the
Nurse Station responsible for each patient. The prescription is written by the doctor and sent to
the pharmacy where the pharmacist reviews the prescription, checks the patient drug file to
determine the appropriateness, such as allergies the patient may have or errors in the
prescription (i.e. labor inducement medication prescribed to a male patient). The pharmacist
then fills the order if the dosage is safe, there are no known patient allergies to the drug, and
the drug does not interact with other drugs the patient is taking.
If the pharmacist decides not to fill the order the doctor is contacted and advised of the
problem. The doctor then may decide to have the order filled anyway or the doctor may write
another prescription and resubmit it to the pharmacy.
Once the prescription is filled a label is generated with the patient information (patient ID
number, patient name, room number, doctor name etc), prescription information (drug name,
amount dispensed, dosage) and medical information (instructions). The label is put on the drug
container. The Patient ID and new drug information (drug, dosage, RX #) are entered by the
pharmacy into the Patient Drug File. The patient ID number, drug name, amount dispensed
and cost of the drug are entered by the pharmacy into the on-line cost center system. The drug
container (with drug) and the corresponding order are then sent to the appropriate Nurse
Station to be administered to the patient
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From Narrative to Use Case
• Once the usage narrative is written and validated,
it can be used as the foundation for a use case
• Employing our use case template, the pharmacy
usage narrative might produce the following use
case.
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Rx System Use Case
Main Success Scenario
1. Doctor enters Rx into system
2. System checks Rx for accuracy
3. Dispense and send label information to Nurses Station
4. Patient receives Rx
5. System updates Billing and Patient DB
Needed Extensions:
2a. System detects inaccuracy
2b. System sends review back to doctor
2c. Doctor resends RX (with or without changes)
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Rx System Use Case (continued)
Other Extensions/Exceptions
1a. Doctor not authorized or this patient
1a1. Rx denied
2a. System detects allergy conflict
2a1. Sends Rx back to doctor
2b. System detects Rx interaction
2b1. Sends Rx back to doctor
2c. System detects Rx duplicate dose
2c1. Sends Rx back to doctor
2d. System detects low or no inventory
2d1. Sends Rx back to doctor.
3a. Rx sent to wrong Nurses Station
3a1. Nurse denies/refuses Rx
3a1a. Sends Rx back to doctor
4a. Patient status changed
4a1. Nurse denies/refuses Rx
4a1a. Sends Rx back to doctor
Special Conditions:
Total system failure or Power loss
** Revert to manual system
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