Must To Know - Fast Track

Question 1

Unit prefix in metric system of units denoting a factor of 1 million (1 x 10^6).

Answer 1

Mega

Question 2

Constant error

Answer 2

Error where there is continual difference between test and comparative method values.

Question 3

Proportional Error

Answer 3

Error where difference between test and comparative method values are proportional to analyte concentration.

Question 4

3:3

Answer 4

Ratio of warning to mandatory Westgard rules.

Question 5

Levi-Jennings

Answer 5

1. QC chart that demonstrates the Westgard rules.

2. Most widely used QC chart in the clinical laboratory.

Question 6

Youdin Twin Plot

Answer 6

QC chart that is used to compare results to different laboratories.

Question 7

CuSum Graph

Answer 7

Plot that gives the earliest indication of a trend.

Question 8

Accuracy

Answer 8

Closeness of measured values to the true value.

Question 9

Sensitivity and Specificity

Answer 9

1. Measures of the diagnostic accuracy of the test.

2. Important criteria in evaluating instruments.

Question 10

Diagnostic Sensitivity

Answer 10

1. Ability to detect the presence of the disease.
2. Indicates the ability of the test to generate more true (+) and few false (-) results.
3. Reflects the ability of the method to detect true (-) result with very few false (+) results.

Question 11

Positive Predictive Value (PPV): Function

Answer 11

Indicates the number of patients with an abnormal test result who have the disease.

Question 12

Positive Predictive Value (PPV): Formula

Answer 12

(true positives)/(true positives + false positives)

Question 13

Negative Predictive Value (NPV): Function

Answer 13

Indicates the number of patients with a normal test result who do not have the disease.

Question 14

Negative Predictive Value (NPV): Formula

Answer 14

(true negatives)/(true negatives + false negatives)

Question 15

Central tendency; Dispersion

Answer 15

Parts of descriptive statistics.

Question 16

Variance, SD, CV, Range

Answer 16

Measures of dispersion.

Question 17

The lower the CV, the _____ the precision.

Answer 17

higher

Question 18

Mean

Answer 18

The average of a given set of values.

Question 19

Median

Answer 19

Middle or midpoint of distribution.

Question 20

Mode

Answer 20

Most frequent observation in a set of data.

Question 21

Mean, Median, Mode

Answer 21

Normal Gaussian distribution curve.

Question 22

Proficiency Testing (EQA)

Answer 22

Evaluation of method performance by comparing results with other lab.

Question 23

Delta check

Answer 23

Comparison between patient’s most recent result and previous determined value.

Question 24

Good Standard Curve

Answer 24

1. Line is straight
2. Line connects all points
3. Line goes through the origin of x and y axis

Question 25

There is perfect correlation of values in linear regression if value falls on __.

Answer 25

1

Question 26

Point of care testing

Answer 26

Test performed usually by non-laboratorian personnel (nurses, RTs, etc.)

Question 27

Specimen used for point of care testing (POCT)

Answer 27

Capillary blood

Question 28

QC of POCT instruments should be done ___________________.

Answer 28

once each day of use

Question 29

Clerical error

Answer 29

Usual cause of error in the laboratory

Question 30

Colligative properties

Answer 30

vapor and osmotic pressure; boiling and freezing points

Question 31

Spectrophotometer

Answer 31

Instrument that uses diffraction gratings (as commonly used monochromators).

Question 32

Beer’s law

Answer 32

Mathematically establishes relationship between concentration and absorbance.

Question 33

Formula for the concentration of an unknown sample (using spectrophotometer)

Answer 33

1. (Au/As) x Cs

2. Gold/Arsenic x Caesium

Question 34

Visible region

Answer 34

400nm - 700nm

Question 35

UV region (very short wavelength)

Answer 35

<400nm

Question 36

IR (infrared radiation) region

Answer 36

> 700nm

Question 37

Tungsten lamp

Answer 37

Light source in the visible region.

Question 38

Light sources in the UV region:

Answer 38

1. Mercury arc
2. Deuterium lamp
3. Hydrogen lamp
4. Xenon lamp

Question 39

Light sources in the IR region:

Answer 39

1. Merst Glower

2. Glober (silicone carbide)

Question 40

Photomultiplier tube

Answer 40

Most common and most sensitive photodetector.

Question 41

Nephelometry

Answer 41

Detects light scattered towards a detector.