Extras for test 1 (intro stuff)

Question 1

What is the type of laboratory used by the campus clinic?

Answer 1

Commercial laboratory like quest diagnostics.

Question 2

Name 5 indications for ordering laboratory tests?

Answer 2

1. Confirmation of a clinical impression or establishment of a diagnosis. 2. Rule out a diagnosis. 3. Monitor therapy. 4. Establish a prognosis. 5. Screen for health; preventative medicine.

Question 3

What is wellness screening?

Answer 3

Testing asymptomatic individuals who are basically healthy.

Question 4

What type of diseases should be screened for with a wellness screening test?

Answer 4

prevalent, can be detected before clinical findings develop, are treatable, have harmful consequences if left untreated.

Question 5

What is acuracy and what is percision?

Answer 5

Acuracy- Correctness. How close a test result comes to the true biologic value. Percision- reproducability, how consistant a test result is via multiple testing of the same specimen.

Question 6

What is sensitivity and specificity?

Answer 6

Sensitivity- True-positive, A highly sensitive test will rule negatives out. Specificity- True-negative, A highly specific test will rule positives in.

Question 7

In order to detected a disease a tests needs maximum what?

Answer 7

Sensitivity.

Question 8

If a test has a very high sensitivity what will specificity be like and what will this mean?

Answer 8

specificity will probably be low, and this results in healthy people being labeled as sick.

Question 9

A good screening test will have high what?

Answer 9

High sensitivity so it will catch almost all true-positives, but it will include people who are not sick.

Question 10

What type of test will have a high specificity?

Answer 10

A confirmatory.

Question 11

What type of test is used when there is high clinical evidence of a disease?

Answer 11

A highly specific.

Question 12

What are reference ranges?

Answer 12

Patients test results are reported along with a numerical range of test values that are found in healthy individuals.

Question 13

How are reference ranges RR established?

Answer 13

Testing on a large number of healthy individuals, then perform a statistical analysis and the results ideally represent a gaussian distribution.

Question 14

Where will the healthy numbers come from in a RR?

Answer 14

plus or minus 2 standard deviations and this will include 95% of the healthy people so 5% of healthy people will be outliers.

Question 15

RR are of most value when?

Answer 15

When there are age, gender, and population specific.

Question 16

What are the test result values given as?

Answer 16

In USA- conventional units. Everywhere besides the USA- SI units or International units which are purely metric.

Question 17

What are the host factors that add variablity to test results?

Answer 17

age, gender, race.

Question 18

What is a coefficient of variation (CV)?

Answer 18

a statistical evaluation to determine if the variation of test results from multiple analyses of the same sample is acceptable. The lower the CV the better.

Question 19

What will make a CV high?

Answer 19

Analytic variation due to methodology. So manual methods can have a CV of 10-15% and automated CV are a few %.

Question 20

Give some examples of improper patient instructions that can be sources of error in laboratory testings?

Answer 20

Poor patient compliance with fasting vs. non-fasting. Collection of specimen. Exercising prior to test.

Question 21

What is a profile or panel testing?

Answer 21

Collection of different tests related to a particular organ, organ system, or disease group.

Question 22

Panels or profile tests allow for what?

Answer 22

Lots of tests at low costs, they help with pattern recognition.

Question 23

What is the problem with panels or profile tests?

Answer 23

Each test adds an increased probability of an increased number of abnormal test results in healthy patients.