post mid 3.8 - 5 both slides and manual

Question 1

Westgard rules are rules that define

Answer 1

specific limits for control values

Question 2

If a control value violates
a rule by exceeding the limits, an error in X has been detected and the results on
patient samples analyzed concurrently cannot X

Answer 2

measurement

be released to the physician

Question 3

once problem is fixed what is the last step

Answer 3

Patient and controls would be rerun to ensure accurate and precise results

Question 4

To interpret the Westgard shorthand

the first number is the number of :

The next number refers to the:

Answer 4

-quality control results that violate the rule

• s level that is being violated

Question 5

1-2s

what is it
type of violation
what if there are other issues

Answer 5

-One control value exceeds the mean by more than 2s but less than 3s.

-Warning

-If there is an error or violation detected the technologist must repeat the QC for that
level or run and perform troubleshooting corrective actions

Question 6

1-3s

Answer 6

One control value exceeds the mean by more than 3s in either the upward or downward direction.

(Random Violation)

Question 7

2-2s

what is it
2 appications

Answer 7

two consecutive control values exceed the mean by more than 2s. These two controls must be consecutive and lie in the same direction from the mean (upward or downward).

(Systematic Violation)

2 applications to this rule:
Within run (same day) and across run (day to day

Question 8

R-4s

Answer 8

The total difference between two levels of controls within a single run is 4s or greater.

Applied only with the current run between two control levels.

(Random Violation)

Question 9

4-1s:

what is it
type of violation
application 2

Answer 9

Four consecutive control values exceed the mean by more than 1s.

(Systematic Violation)

These 4 controls must be consecutive and lie in the same direction from the mean.

2 applications:
* Across control material (day-to-day)
* Within control material (same day with 2 or more levels)
4 consecutive control values outside 1SD on the same side of the mean

Question 10

10x:

Answer 10

Ten consecutive control values exceed the mean in the same direction.

(Systematic Violation)

2 applications:
* Across one level of control material (day-to-day)
* Within control materials (Level 1, 2, and 3 control results in combination

Question 11

1-2s rule is a flag that indicates a possible change in relative

Answer 11

accuracy and precision

Question 12

The justification for using the 1-2s rule as a flag and not a violation is based on the

Answer 12

95% confidence limits

1 in every 20 assay values will be
outside of our 95% confidence limit. Chances are, the next time we run our control, its
value will be within the 95% confidence limit.

Question 13

T or F

It is common lab practise to repeat the control when there is no data from the previous day to rule out other violations.

Answer 13

T

Question 14

The violation of the 1-3s rule is always reason for rejection bc

Answer 14

As mean +/ 3s
takes in 99.7% of
all data, we can be highly certain that an error has occurred in measurement.

Question 15

2 advantages of westguard rules

Answer 15

-Distinguishes between random and systematic error

-Westgard rules can indicate the direction that the investigation of a systematic error
should take

Question 16

random error is one that is (1)

in LJ vs WG

Answer 16

indeterminable

LJ-a random error is seen as a control value which is significantly different from the other values
-1-3s and the R-4s rules indicate a random error

Question 17

A systematic error is an error that is (2)

in LJ vs WG

Answer 17

predictable and identifiable

LJ=trend or a shift
WG= 2-2s, 4-1s and the 10x r

Question 18

Cumulative Charts (Cusum) sensitive means to detect:

Answer 18

systematic error

Question 19

Corrective Actions

Answer 19

Any violation of the Westgard rules requires further investigation

Question 20

Generalized Flow Chart for Corrective Actions using Multirules

for 1-2s
step 1,
2 random error:
3 Systematic error
4 final step
5 if nothing works

Answer 20

-for 1-2s if you have prior data to analyze you can just do that, otherwise a repeat of QC is done

step1-is a rejection occurred analyzed the control sample that was out, for human errors like the correct bottle, if only one QC is out then it is not the bottle

step 2-for random repeat QC and accept QC if repeat is ok.

step 3-for systemic Troubleshoot and identify the source of error

step 4: Repeat the QC after troubleshooting

Step 5: If the control value is still out of range, another laboratory professional with more technical
experience may be able to help. The last step in this series of corrective actions should be to obtain
help from an expert, usually a manufacturer’s technical representative. Most manufacturer’s have a
hotline number

Question 21

if it is a systematic error what 3 things do we look at

Answer 21

• Problem with QC vial (end of bottle, expired, new lot, wrong vial) – repeat using fresh vial of QC
• Instrument problem (humidity, debris, tubing, probe, maintenance) – correct the instrument problem
• Reagent problem (not mixed properly, expired, bubbles in reagent, new lot) – correct the
  reagent problem and calibrate the reagent.

Question 22

Mean of Normals (Application of Bull’s Algorithm)

what is it
what should remain constant
type of errors detected

when is it most often used

Answer 22

-In this particular QC tool, the average of all the patients’ results (at least 250) that fall within the normal reference range is calculated.

-The mean target value should remain constant

-detects only systematic erroors

-This QC method is often applied
in the hematology laboratory, in particular, to the red cell indices, MCV, MCH and MCHC

Question 23

Maintenance refers to

Answer 23

the activities associated with keeping laboratory instrumentation in good working order.

Question 24

Preventative maintenance

-objective

Answer 24

-incorporates those same activities with perhaps a few more specific ones related to an instrument.

-object is to decrease the chances of that instrument breaking down and having to call in a service

-Preventative maintenance should be part of the daily routine of any laboratory personnel

Question 25

Some of the current models of instrumentation are programmed to do self-checks. These may
include

Answer 25

electrical checks, flushing of valves, priming of reagents, analyzing a control, etc.

Question 26

Material management

Answer 26

the acquisition and utilization of supplies to ensure both availability and cost effectiveness

Question 27

Inventory Control involves:
(4)
what are standing orders

Answer 27

1. Ordering supplies in sufficient quantities
2. rotating stock
3. checking of stock levels: want max amounts
   standing orders: constant used, or lower shelf life items that are ordered based on an an established scheduled
4. minimize the cost, not to much or too little ordered

Question 28

When lot numbers of control material
change, it must be analyzed

Answer 28

to obtain new target values (means) for the constituents (all the tests or assays being run using that control) before incorporating it in the daily routine for any method

Question 29

effective inventory control maintains X and minimizes Y

Answer 29

quality assurance

one of the analytical variables

Question 30

An important part of quality assurance involves the analysis of the new method to ensure its X as well as for its ability to X

Answer 30

accuracy and precision

correctly diagnose disease

Question 31

non-statistical test for linearity and several statistical tests

Answer 31

• tests for significance: precision and accuracy or reliability
• correlation and
• diagnostic method evaluation

Question 32

Linearity checks

Answer 32

• preliminary checks on the accuracy of the new method

-involves assaying a series of increasing concentrations of standards with the new method

-include concentrations at the high and the low end of the manufacturer’s listed range of linearity

-If the method is linear, it should hold true when specimens are diluted

-Do the data points produce a line with a 45 degrees

Question 33

Tests for Significance 3

Answer 33

Probability
Precision: F-Test
Accuracy: Student t-Test

Question 34

Probability

Answer 34

Probability is a means of expressing the prediction of outcome, or the chances that something
will happen

Question 35

Tests for significance are used to compare

Answer 35

the accuracy and precision of two methods

Question 36

If we are considering bringing a new method into the lab, we need to evaluate its reliability
against X or Y

Answer 36

he old method or against a reference method

Question 37

We compare the4 things of the 2 methods

Answer 37

linearity, accuracy, precision and correlation coefficient of the two methods

Question 38

X % zone is known as the significance level

Answer 38

5

which allows us to make a decision as to
whether or not the two sets of data are the same

Question 39

We decide on the similarity of the two methods
by using a calculation involving the probability that

Answer 39

the two normal distribution curves representing the data are the same

Question 40

Null Hypothesis:

Answer 40

there is no significant difference
between two sets of data. The 2 sets of data are close enough to satisfy
our 95% (P0.05) confidence limits.

Question 41

Alternate Hypothesis

Answer 41

here is a significant difference between two sets of data and
their similarities are not within the allowable 95% (P0.05) limits.

Question 42

P value:

Answer 42

probability of being wrong when a test statistic proves the null hypothesis.

Question 43

Our goal is to prove the X hypothesis

Answer 43

null

Question 44

cut-off point for proving our null
hypothesis which is selected as the degrees of freedom

Answer 44

(n-1)

Question 45

F-Test

Answer 45

-used to compare the precision of a new method to the old (or reference) method

compares the variance of two methods and judges whether the two variances are essentially the same.

Question 46

Student t-Test

Answer 46

used to compare the accuracy of a new method or instrument to a reference method or to the old method

This is done by comparing the means of the two methods

Question 47

Correlation Coefficient

Answer 47

compare the results of one method to those obtained by a second method.

It determines the relationship between any two items, provided the items have a numerical value.

formula for the correlation coefficient is based on the formula for linear regression by least
squares

The closer the “r” value is to 1, the better the correlation.
A positive “r” value indicates that the line slopes upward to the right.
A negative “r” value indicates that the line slopes downward.

Acceptable correlation produces a 45 angle
and a slope of ±0.92 – 1.08

Question 48

Diagnostic Method Evaluation

Answer 48

new method also be evaluated for its ability to correctly diagnose disease

true positive, TN, FP, FN

Question 49

Sensitivity of a Test

Answer 49

If we can calculate 100% sensitivity then we have 0 false negatives.
Sensitivity is usually expressed to one decimal place.

positive controls
detects low amounts

Question 50

Specificity of a Tess

Answer 50

e. If we have 100% specificity, we have 0 false positives. Specificity is usually
expressed to one decimal place.

Question 51

Predictive Value of a Positive Test

Answer 51

ability of a test to correctly diagnose disease in the population being tested.
It asks the question, what is the frequency of diseased patients out of positive tests?

compares the prevalence of the disease with the sensitivity and specificity of the test

If a test has 100% predictive value, we have zero false positive results

Question 52

Post-Analytical Checks

Answer 52

verifying quality in those variables that can have an impact on test results after the testing of patients’ samples is complete

These post analytical checks are the final
review before results are released outside the lab and serve as an important aid to the other
internal quality assurance methods used

Question 53

Clinical Correlation

Answer 53

simple check of the patient’s test results to the clinical diagnosis

Question 54

Correlation with Other Laboratory Tests

Answer 54

e, errors can be identified and corrected before the report is
released to the patient’s file

Question 55

Intralab Duplicates monitor for which errors?

Answer 55

dividing the same specimen into two aliquots and having each aliquot analyzed for all the same tests ordered. The differences between the duplicates can
be plotted on control charts to aid in monitoring.

Duplicates obtained from more than one method monitor both random and systematic
error.

Question 56

Delta Checks

Answer 56

patient has had the same lab tests done on more than one occasion, the delta checks or
variations between the previous test results can be compared to see if they fall within the limit
allowed for normal changes.

Question 57

Limit Checks and Critical Values

Answer 57

checked beyond the reference ranges (impossible or
absurd results) or incompatible with life (critical results)

caused by clerical errors, short sampling or clot formation, improper identification of fluid being analyzed or improper specimen collection

Question 58

Mean of Normals

Variation demonstrates what error

Answer 58

mean of the normal patients’ values can
be calculated

A variation in this mean will demonstrate a systematic error but will not show a random error

not a substitute

Question 59

Reporting Mechanisms

Answer 59

reporting of results to physicians has a direct outcome on the care of the patient. Areas
where problems can be found in reporting that can have an effect on patient outcomes

Question 60

Record Keeping

Answer 60

refers to the maintenance of records related to patient results

importance of good record keeping is to be able to refer back to previous results and so
check the patient’s history upon re-admittance or transfer to another healthcare facility

Question 61

Test Completion Checks

Answer 61

This check is to verify that all tests ordered are completed before releasing the results

Question 62

Reflex Testing Protocols

Answer 62

refers to the automatic “reflex” of one (1) result
triggering another test to be performed.

Question 63

external QC

External Agencies and Programs

Answer 63

To ensure more complete objectivity, laboratories will register in external QA programs.

This may also be a requirement of the accreditation process

results are submitted to the agency which will provide an evaluation based on the target results

Question 64

Company Sponsored QC Programs

Answer 64

supply laboratories with daily control material which they analyze and send statistical or raw data on the daily control values to the company at the end of each month

Question 65

company provides the laboratory with information on the amount of

Answer 65

long term inaccuracy and imprecision that may be occurring

information on the closeness of its results on the control pools to that of peer laboratories using
the same control materials

Question 66

Some examples of company sponsored QC programs are

Answer 66

Beckman Coulter’s EQAP program for
hematology controls and Biorad’s UNITY program

Question 67

Proficiency Testing

Answer 67

most common type of external QC involves testing biological samples submitted to a
laboratory by an outside agency.

unknown samples “blind”

results are sent back to the agency which compares the results from the laboratory with the known value or interpretation of the samples and informs the lab of the closeness of the test result to the true value or interpretation

requirement for accreditation

usually must be purchased in addition to daily controls

Question 68

The standard deviation for proficiency testing is referred to as

Answer 68

standard deviation interval or SDI

to determine the amount a lab’s result may differ
from the average of the results from a group of peers

Question 69

CAP Surveys

Answer 69

most developed and sophisticated proficiency testing program is the one by the College of
American Pathologists or CAP Survey

participants receive a number of specimens for analysis and return their
results to the CAP Computer Center

Any reported results that differ exclusively from the mean value
are flagged to alert the participant of possible analytical error.

quarterly and annual reports to participants to provide other means of providing an overview of
the laboratory QC.

Question 70

Accreditation

Answer 70

Accreditation is not government run but is an independent group of experts that examines every
medical laboratory to ensure organizations demonstrate competence to manage and perform the
activities defined by Quality Management Systems ISO9001. Accreditation provides the medical
community and public with confidence that the highest quality standards are being met.

Question 71

Lab Licensing

Answer 71

-provincial government set of rules

-dministered by the respective Ministry of
Health that regulate the laboratory facility itself and grant permission to that facility to engage in
the business of testing patient samples.

-The provincial College of Physicians & Surgeons
is usually the group given the authority to administer the accreditation process which establishes
the standards and QA policies.

Question 72

Provincial Programs

Answer 72

Some provinces may have specific regional QA programs in place for monitoring laboratories

Question 73

Professional Regulation

Answer 73

-protect the public from incompetence and
misconduct

Question 74

These provincial regulations can be in two forms. The “right to title”

Answer 74

a certain
qualification based on an established training program acts as a recognized standard and is assigned to a certain occupational group.

example the CSMLS certification process serves as
the minimum recognized standard in most provinces in Canada

“No person other than a
member of the SSMLT shall use the title medical laboratory technologist or registered
medical laboratory technologist or any word, title or designation, abbreviated or otherwise, to
imply that the person is a member.”

Question 75

Another form of professional licensing is the “right to practice”

Answer 75

in which a certain occupational
group is given, not only all the benefits of the “right to title”, but also the authority to restrict
others from performing functions that are deemed exclusive to their practice. There are only a
few occupational groups that have this right—doctors and lawyers for example