LABORATORY STATISTICS

Question 1

MEASURES OF CENTER/ central tendency

Answer 1

Mean, median, mode

Question 2

average or arithmetic mean

Answer 2

Mean

Question 3

midpoint of a data set after the values have been rank-ordered

Answer 3

Median

Question 4

most frequently occurring value in a data set

Answer 4

Mode

Question 5

MEASURES OF SPREAD/ Variability/ Distribution

Answer 5

Standard Deviation , Coefficient of Variation & Range

Question 6

distribution of data points around the mean

Answer 6

Standard deviation

Question 7

Square of SD

Answer 7

Variance

Question 8

Best indicator of precision

Answer 8

Coefficient of variation

Question 9

difference between the highest and lowest values

Answer 9

Range

Question 10

Data points are distributed symmetrically around the mean (bell-shaped curve) with most values close to the center

Answer 10

GAUSSIAN/NORMAL DISTRIBURION

Question 11

Mean, median, and mode are identical

Answer 11

GAUSSIAN/NORMAL DISTRIBURION

Question 12

Empiric rule

Answer 12

68-95 - 99.7% rule

Question 13

Rule of thumbs

Answer 13

CV = < 10 %

Question 14

REFERENCE INTERVAL STUDIES

Answer 14

Verifying a reference interval & Establishing a reference interval

Question 15

done when there is no existing RI for an analyte or when transference studies fail

Answer 15

Establishing a reference interval

Question 16

Establishing a reference interval requires at least _______ study individuals; RI is set based on the ______________________

Answer 16

120; 95% confidence interval
CI = x̄ + /- 2s

Question 17

done to confirm the validity of an existing or published RI for an analyte

Answer 17

Verifying a reference interval

Question 18

Verifying a reference interval requires at least ____ study individuals; RI is adopted if _____ of the subjects fall outside the range

Answer 18

20; < 10%

Question 19

first step in method evaluation; usually done by running two control materials twice a day over a 10-day period

Answer 19

Precision study

Question 20

involves spiking a sample with a known amount of an analyte and determining how much of it can be detected by the method in the presence of other compounds in the matrix

Answer 20

Recovery study

Question 21

compares the MEANS of two groups of data or the ACCURACY of two methods

Answer 21

T test

Question 22

compares the STANDARD DEVIATION (SDs) of two groups of data or the PRECISION of two procedures

Answer 22

F test

Question 23

used to compare two methods using the best fit line through the data points

Answer 23

Linear regression

Question 24

Independent variable = reference method

Answer 24

X axis

Question 25

Dependent variable = new method

Answer 25

Y axis

Question 26

ability of a method to detect the smallest concentration of an analyte

Answer 26

Analytical sensitivity

Question 27

ability of a method to detect only the analyte of interest

Answer 27

Analytical specificity

Question 28

Diagnostic Efficiency

Answer 28

1) Diagnostic sensitivity 2) Diagnostic specificity 3) Positive predictive value 4) Negative predictive value

Question 29

ability of a test to detect a given disease or condition; proportion of individuals with the disease who have a positive test result

Answer 29

Diagnostic sensitivity

Question 30

ability of a test to detect the absence of a given disease or condition; proportion of individuals with no disease who have a negative test result

Answer 30

Diagnostic specificity

Question 31

probability that a positive test result indicates disease; proportion of individuals with a positive result who truly have the disease

Answer 31

Positive predictive value

Question 32

probability that a negative test result indicates absence of disease; proportion of individuals with a negative result who truly do not have the disease

Answer 32

Negative predictive value

Question 33

management philosophy and approach that focuses on processes and their improvement as the means to satisfy customer needs and requirements

Answer 33

TOTAL QUALITY MANAGEMENT

Question 34

Five Q Framework

Answer 34

Quality Planning (QP) Quality Laboratory Process (QLP) Quality Control (QC) Quality Assurance (QA) Quality Improvement (QI)

Question 35

Quality Improvement Tools:

Answer 35

Six Sigma (6 σ) & Lean

Question 36

Reduction of defects to near zero

Answer 36

Six Sigma (6 σ)

Question 37

necessary to establish measures for performance monitoring, and ensure that the performance achieved satisfies quality requirements.

Answer 37

Quality planning

Question 38

include analytical processes, general policies, practices, and procedures that define how all aspects of work are done.

Answer 38

Quality laboratory process (QLP)

Question 39

involves statistical control procedures as well as nonstatistical checks

Answer 39

Quality control (QC)

Question 40

concerned with broader measures of laboratory performance including TAT, patient identification, specimen collection, and test utility.

Answer 40

Quality assurance (QA)

Question 41

provides a structured problem-solving process to help identify the root cause of a problem and a remedy for that problem.

Answer 41

Quality improvement (QI)

Question 42

Reduction of non-valued activities (wastes)

Answer 42

Lean

Question 43

Categories of wastes

Answer 43

Defects Overproduction Waiting Non-utilized talent Transport Inventory Motion Excess processing

Question 44

Steps in six sigma

Answer 44

DMAIC Define Measure Analyze Improve Control

Question 45

include test requisition, patient preparation, patient identification, specimencollection, labeling, specimen transport, specimen reception, handling, and preparation

Answer 45

Pre-analytical

Question 46

include reagents, preventive maintenance of equipment, calibration, analysis of samples, and quality control

Answer 46

Analytical

Question 47

include verification of calculations and reference ranges, flagging and notification of panic/critical values, delta checks, reporting of results

Answer 47

Post-analytical

Question 48

an algorithm in which a current laboratory result is compared with results obtained on a previous specimen from the same patient

Answer 48

Delta check

Question 49

Quality control

Answer 49

Reliability, accuracy, precision, internal quality control & external quality control

Question 50

ability to maintain accuracy and precision over an extended period of time during which equipment, reagents, and personnel may change

Answer 50

Reliability

Question 51

Closeness of the result to the true or actual value

Answer 51

Accuracy

Question 52

Ability to produce a series of results that agree closely with each other

Answer 52

Precision

Question 53

Commonly expressed in terms of coefficient of variation

Answer 53

Precision

Question 54

Also call repeatability reproducibility

Answer 54

Precision