Method Eval Flashcards
1
Q
The measure of center, spread and shape.
A
Descriptive statistics
2
Q
Assessment of data dispersion, or spread, allows
laboratorians to assess the predictability (and the
lack of) in a laboratory test or measurement.
A
Descriptive statistics
3
Q
Most commonly used and often measure
A
Mean
4
Q
Mean is also called as
A
Average
5
Q
Add all the given value, then divide it to the number of the values
A
Mean
6
Q
is used in many statistical
formulas.
A
Summation sign
7
Q
the mean of a specific dataset is
called
A
X or x bar
8
Q
The “middle” point and is often used with skewed
data so its calculation is not significantly affected
by outliers.
A
Median
9
Q
It is the middle of the data after the data have been
rank ordered.
A
Median
10
Q
It is the value that divides the data in
half.
A
Median
11
Q
values are rank ordered
from least to greatest and the middle value is
selected.
A
Median
12
Q
Rarely used as a measure of the data’s center but is
more often used to describe data that seem to
have two centers
A
Mode
13
Q
Mode is also called as
A
Bimodal
14
Q
is the most frequently occurring value in
a data set.
A
Mode
15
Q
it is seldom used to describe
data
A
Mode
16
Q
it is referred to when in reference to the
shape of data, a bimodal distribution
A
Mode
17
Q
it is referred to when in reference to the
shape of data, a bimodal distribution
A
Mode
18
Q
There are four commonly used
descriptions of spread:
A
Range
Standard deviation
Coefficient of variation
Standard deviation index
19
Q
It is a common type of distribution for variable
A
Bell curve/ normal distribution/ gaussian curve
20
Q
The easiest measure of spread to understand
A
Range
21
Q
is simply the largest value in the data
minus the smallest value, which represents the
extremes of data one might encounter.
A
Range
22
Q
is often a good measure of dispersion
for small samples of data.
A
Range
23
Q
is one description of the spread of data.
A
Range
24
Q
It is simply
the difference between the highest and lowest data
points
A
Range
25
To calculate the SD of a dataset, it is easiest to first
determine the variance
Variance
26
is similar to the mean in that it is an
average.
Variance
27
is the average of the squared distances of
all values from the mean:
Variance
28
- is the most frequently used measure of variation.
Standard deviation
29
is the square root of variance
Standard deviation
30
Standard deviation is called
s, SD or σ
31
Another way of expressing SD is in terms of the
Coefficient of variation
32
is calculated by dividing the SD by
the mean and multiplying by 100 to
express it as a percentage:
Coefficient of variation
33
Formula of Coefficient of variation
CV= (SD/M)x 100
34
the __________ the STANDARD DEVIATION (SD) is and
the LOWER the COEFFICIENT OF VARIATION (CV) is,
the MORE PRECISE the data is.
LOWER
35
the LOWER the STANDARD DEVIATION (SD) is and
the LOWER the COEFFICIENT OF VARIATION (CV) is,
the MORE ___________ the data is.
PRECISE
36
preferably used to determine errors/variations
Levey-Jennings Chart
37
Solution For accuracy
Standard solution
38
A solution of known characteristics and of known
value or whose concentration is
accurately known
Standard solution
39
It is composed of one known constituent only and
used as a basis of reference for the calculation of
the value of the unknown.
Standard solution
40
100% pure solution
Standard solution
41
Serve as a reference for unknown
Standard solution
42
Choose the standard nearest to the unknown
Standard solution
43
purity of standard solution
100% +0.02%
44
Concentration of the unknown
Standard solution
45
For precision solution
Control solution
46
A solution (either commercially or non-
commercially prepared) composed of several
known constituents which can be run
simultaneously with the test to check the accuracy
of the results.
Control solution
47
Stable for a long period of time
Control solution
48
2 forms control solution
Liquid or lyophilized
49
WHEN TO PERFORM
QUALITY CONTROL
- Beginning of each shift (Daily testing)
- New instrument
- After an instrument is serviced
- When reagent lots are changed
- After calibration and
- Whenever patient results seem inappropriate
*Lot number changes annually
*Calibration must be followed by control
50
A solution without the specimen.
Blank solution
51
It sets the spectrophotometer reading to zero.
blank solution
52
Distilled water as reagent blank
vs. Specific reagent per analyte
Blank solution
53
Three types blank solution
Water blank
Sample blank
Reagents blank
54
Type of Blank solution remove interference
Sample blank
55
e.g. of interference sample balnk
Hemoglobin - hemolysis
Lipid- turbidity
Bilirubin- increase
56
Type of blank solution set reading to zero, for
correcting color interference
Reagent blank
57
Errors in Quality Control
Variation
58
The fundamental basis of any statistical analysis.
Mechanial problems
Contaminated reagent
Technical errors
59
The mathematical result when the summation of data is divided by the total number of
data
Arithmetic value or mean or average
60
It is the statement of the extent of variation in any series of measurement
Standard deviation
61
It is a measure of the distribution range of values around the mean value or average
Standard deviation
62
Measure of spread of data.
Standard deviation
63
It is the percentile expression of the mean which is measure of the relative magnitude of
variability.
Coefficient of variation
64
- It is the ratio of the standard deviation over the mean expressed in percent
Coefficient of variation
65
It is a statement of variability and measures the significant differences between groups of
data.
Variance
66
Most commonly used histogram/charts
Shewhart-levey jenning chart
67
Shewhart-jevey jenning chart also known as
Levey-jenning chart, s-l/j or dot chart
68
It will group any series of measurement in the same sample in
a cluster around the mean in a bell shaped curve
gaussian curve
69
Histogram show the confidence limit
Gaussian curve
70
Gaussian curve also known as
Gaussian distribution curve, normal
distribution curve
71
Gaussian curve is commonly known as
Bell-shaped curve
72
Plotted with the accumulated differences from the mean of
individual values with the middle value being zero.
Cumulative sum graph
73
Value is zero and not the mean.
Cumulative sum graph
74
Cumulative sum graph also known as
Cusum graph
75
Histogram/chart with x and y axis
Youden plot
76
A 2-mean chart drawn at right angles to one another with the
one set of values on one axis another set of values on the other
axis.
Youden plot
77
Youden plot also known as
Twin plot, two mean chart or two way average chart
78
INTERPRETATION OF RESULTS: when the values of the control fall within the confidence limit
In control
79
INTERPRETATION OF RESULTS: when the values of the control fall outside the confidence limit.
Out control
80
Westgard rule Developed by
James westgard
81
uses a multiple QC procedure as decision criteria to
determine if an analytic run is in control
Westgard rules
82
States that 1 controlled value
exist ± 2 standard deviation from the
mean.
1 2 s
83
Serves as a warning rule that
will alert the med tech for possible
problem
1 2s error
84
States that 1 controlled value
exist ± 2 standard deviation from the
mean.
1 2s error
85
States that 4 consecutive controlled
values exceeds ± 1 standard deviation
and on the same side of the mean
4 1s error
86
2 consecutive controlled values
exceed the same limit, either +2SD
or -2SD
2 2s error
87
1 controlled value is greater than - 2
SD; other value exceeds + 2 SD
R 4s error
88
The numerical difference
between this 2 controlled values
within the same run exceeds 4 SD
R 4s error
89
10 consecutive controlled
value lies in the same side of the
mean
10x error
90
No requirement as to the size of SD
10x error
91
Violation of the rule
is associated with: 1 2s error
None
92
Violation of the rule
is associated with: 1 3s error
Random error
93
Violation of the rule
is associated with: 4 1s error
Systematic error
94
Violation of the rule
is associated with: 2 2s error
Systematic error
95
Violation of the rule
is associated with: R 4s error
Random error
96
Violation of the rule
is associated with: 10x error
Systematic error
97
is formed by controlled
values that is either increase or
decrease for at least 6 consecutive
days
Trend
98
This indicates a gradual loss of
reliability in the test system
Trend
99
Formed by controlled values that
distribute themselves on one side of
the mean for at least 6 consecutive
days
Shift
100
Represents sudden or abrupt
change in the test system
performance
Shift
101
Trend main cause
deterioration of
reagent
102
Shift main cause
improper calibration
of machine
103
Range of values for a given constituent in healthy individuals (normal value)
Reference value
104
Set of numbers indicating range and values one would expect in a defined population with no apparent clinical problems
Reference value
105
Concept of Gaussian distribution can be directly applied to the discussion of reference values
Reference value
106
POINT OF CARE TECHNIQUE
Objectives:
– 1. Define point of care testing
– 2. Explain what basic structure is required to manage POCT team
– 3. List the common POC applications
107
is defined as medical testing at or near the site of patient
care.
Point of care testing
108
The driving notion behind POCT is to bring the test conveniently and immediately to the
patient.
Point of care testing
109
This increases the likelihood that the patient, physician, and care team will receive the
results quicker, which allows for immediate clinical management decisions to be mad
Point of care testing
110
POCT includes:
-blood glucose testing,
-blood gas and electrolytes analysis,
-rapid coagulation testing,
-rapid cardiac markers diagnostics,
-drugs of abuse screening,
-urine strips testing, etc.
111
Support staff:
1. Director
2. Point-of-care coordinator
3. Designated contacts or trainers in
non-laboratory departments
112
a laboratory scientist or pathologist with a PhD, MD, or DO degree usually
fills this position.
Director
113
the POCC coordinator is responsible for implementing and coordinating
point- of care patient testing and facilitating compliance with procedures
and policies and regulatory requirements.
Point of care coordinator
114
for each units/floor/clinic that performs POCT, it is important to have a
designated contact person or trainer.
Designated contacts or trainers in
non-laboratory departments
115
This person greatly facilitates the efficient POCT program and is a
communication link between the POCC and the testing staff
Designated contacts or trainers in
non-laboratory departments
116
Is the consistent use of the same instrument/reagent/test method for any particular
analyte throughout the designated health care system
Standardization
117
Standardization produces the following benefits:
>Improved patient care
>Decrease cost
>Saves work in time
>Facilitates regulatory compliance
118
Committees Communication:
Networking
119
Committees Selection of device and methods:
review multiple options
120
Implementation
o Instrument manual
o Package inserts for reagent
o Package inserts for quality controls
o Materials safety data sheet
o Sample procedure from vendor
121
Procedure/Policy
• Principle
• Specimen
• Reagents
• Maintenance
• Power
122
Training Checklist
▪ Maintenance
▪ Reagents
▪ QC
▪ Reporting results
▪ Safety
123
Point-of-care applications
Point-of-care glucose
Point-of-care chemistries and blood gases
Point-of-care coagulation
Point-of-care hematology
Point-of-care connectivity
124
is the highest volume POC test in most healthcare institutions.
POC glucose
125
- most frequently electrolytes and/or blood gases.
POC blood gas
126
- the most common POC coagulation test is activated clotting time (ACT)
POC coagulation
127
POC coagulation - the most common POC coagulation test is _______________ (ACT)
activated clotting time
128
- at the present time, only minimal hematology POCT has been available.
POC hematology
129
The spun hematocrit was the most common POC hematology test.
POC hematology
130
was the most common POC hematology test.
spun hematocrit
131
connectivity has been the most significant recent development in POCT.
POC connectivity
132
Accuracy under only
Validation
133
Precision under
– Sensitivity and specificity
– Reportable range/linearity
– Reference range
– Split-sample correlation vs reference method
