Laboratory tests

Question 1

Non invasive tests

Answer 1

• Examines fluids and other substances (eg. urine, exhaled air)
• Obtained without using a needle, tube device or scope to penetrate skin or enter the body

Question 2

invasive tests

Answer 2

• Examines fluids or tissues (blood and tissue samples) obtained by using a needle, tube device or scope to penetrate skin or enter the body.

Question 3

specimen

Answer 3

A sample of a substance that is subjected to laboratory analysis

Question 4

Reference Range

Answer 4

A statistically-derived numerical range obtained by testing a sample of the individuals assumed to be healthy.
The upper and lower range limits are not absolute (eg. normal vs abnormal) but are considered points beyond which the probability of therapeutic significance begins to increase.
“Reference range” is the preferred term versus normal range.

Question 5

Rationale for ordering lab tests

Answer 5

Discover occult disease
Confirm a suspected diagnosis
Differentiate among possible diagnoses
Determine the stage or activity of a disease
Detect disease recurrence
Assess the effectiveness of therapy
Guide the course of therapy

Question 6

screening tests

Answer 6

are a form of secondary prevention intended to detect disease in early stages when most amenable to treatment
(ex.) Pap smears, glucose testing, PSA test
Must be cost-effective and population appropriate.

Question 7

Diagnostic Tests

Answer 7

Diagnostic testing is performed on people:
with signs or symptoms of disease
history suggestive of a specific disease or disorder
following an abnormal screening test

Diagnostic testing is used to confirm: 
a suspected diagnosis
differentiate among potential diagnoses
determine the stage of disease activity
detect disease recurrence
assess and guide therapeutic course