When a person is ill, diagnosis begins with physical examination by a doctor. It may not possible to diagnose a disease only on the basis of physical examination. There are various diagnostic tests to confirm a suspected diagnosis. The clinical/pathological laboratory tests are extremely useful to find out the causes of disease.
The order or lab request contains a list of tests to be performed on one or more patient specimen, for example blood or urine. Each lab has its specific request that contains tests that performed in that lab only i.e. chemistry request, hematology request…etc.
The following items should be included on the lab requisition:
1. Full name: middle name should be included to avoid confusion in the event that there is another patient with the same first and last name.
2. Location: inpatient, room, unit, outpatient, address.
3. Patient’s identification number: this identification can be very useful for instance in the blood bank.
4. Patient age and sex: in evaluating laboratory results, the reference values may differ for age and sex; disease prevalence may be age- or sex-linked.
5. Name(s) of the physician(s): name all of the physicians on the case; “panic values” should be called to the attention of the physician ordering the test; a physician may have some specific test guidelines for his patients.
6. Name of the test and the source: reference values may be different for the different biologic specimens (e.g., serum and CSF glucose
7. Possible diagnosis: essential for evaluating laboratory results and selecting appropriate methodology; (media selection in microbiology).
8. The date and time the test is to be done: some tests must be scheduled by the laboratory; patient preparation and diet regulations need to be considered.
9. Special notation: provide relevant information to assist the laboratory–e.g., medications taken; for hormone assay, the point in the menstrual cycle when the specimen was obtained.