CC1 QUALITY CONTROL P3

• Series of values in the control chart that continue to increase or decrease for at least a period of six consecutive days.

• a progressive drift of the reported values from the prior mean value

TREND

• Values distribute themselves on one side of mean at a constant level for at least six consecutive days.

• It occurs when there is an abrupt change from the established mean value.

SHIFT

Out of range values

OUTLIERS

-determined For each test method and is expressed either in measurement units of analyte.

-based on the quantity error that will negatively affect clinical decisions.

ALLOWABLE ERROR (E.)

graphical representation that display the control observation av a function or time.

QUALITY CONTROL CHARTS

- control result are plotted on the Y-axis (ordinate) vs time on the X-axis (abscissa)

LEVEY-JENNINGS CHART / LEVY

-uses a series of control rules for interpeting data.

• FALSE rejection is kept LOW

• ERROR detection is IMPROVED

WESTGARD MULTIRULE CHART

5 SIX SIGMA

DMACI

Define

Measure

Analyze

Control

Improved

• Hands-on process with the single mantra of improvement

• refer to the goal of reducing defects to near zero (Sigma or Standard Deviation)

SIX SIGMA

DPMO

Defect per million opportunities

anything that does not meet customer requirement.

DEFECT

it is obtain by adding the difference (value from the mean) to this chart of the previous difference

CUMULATIVE SUM (Cusum) CHART

Found in clinical laboratories with microcomputer Q.C programs

DECISION LIMIT CUSUM

- also known as scatter diagram

- information about the nature of the SE can be obtained whe two different control materials have been analyzed.

YOUDEN PLOT

-present information in an efficient graphical format

- accomplished with a simple listing of items.

- use maybe enhanced by incorporating a depiction of the system under analysis into the form

CHECK SHEET

-use to identify factors that have the greatest cumulative effect on the system.

- allow the user to focus attention on a few important factors in a process.

- cumulative frequencies of the relative Frequency data are plotted in descending order

PARETO CHART

-Ishikawa or Fish bone diagram

-used to associate multiple possible causes with a single effect

CAUSE & EFFECT DIAGRAM

represent the effect (quality characteristic that is intended to be improved and controlled)

PRIMARY BRANCH

correspond to major causes that directly relates to the effect

MAJOR BRANCHES

more detailed causal Factors

MINOR BRANCHES

emerging problems in Fish bone diagram what part?

HEAD

- pictorial representation of a process

- used in identitying where errors are likely to be found in the system

FLOW CHART

-provides a simple, graphical view of accumulated data including its dispersion and central tendency

-ease of construction

- provide the easiest way to evaluate the distribution of data

HISTOGRAM

-a substance of known composition, the value of which is established by an analytical procedure different from thet used in the clinal laboratory

• If the clinical procedure is able to duplicate the standard value, then this procedure is accurate

STANDARD

• chemical that is for the highest purity and can be measured directly to produce a substance of exact known concentration

PRIMARY STANDARD

It requires that a primary standard is at least 99.98% pure and that the working standards be 99.95%

INTERNATIONAL UNION OF PURE AND APPLIED CHEMISTRY (IUPAC)

Substance of lower purity whose concentration is determined by comparison to a primary standard

SECONDARY STANDARD

excess non-hemolyzed sera vathouts gross lipemia that are collected daily in the laboratory and pooled for storage in the ref

POOLED CONTROL SERA

either prepared from human serum or from bovine

COMMERCIAL CONTROL SERA

Base products (cow-antigenic property of humans are closely linked with mammals )

BOVINE

• Measures of the center of distribution

• Sum of the values divided by the number of the values

ARITHMETIC MEAN (X)

• Measure of dispersion

• Provides information regarding the spread or scatter of values about the center

VARIANCE (S²)

Measure of dispersion of values around the mean ; square root of variance

STANDARD DEVIATION

• Standard deviation expressed as percentage of the mean

• Used if there is a need to compare relative variability between different sets of data

COEFFICIENT OF VARIATION (CV)

s/ SD

Standard Deviation

x

Sample mean

The middle observation among observed values which are arrange in increasing order

MEDIAN

HISTOGRAM ALSO KNOWN AS?

STORY BOARDS

• A system for reducing waste (non valued activities) especially in production of manufacturing process

• It was conceptualize to improved the automobile industry in terms of the quality and efficacy of automobile production.

LEAN SYSTEM

-it utilizes the 5S and PDCA system to diminish cost by identifying daily work activities that do not directly add to the delivery of laboratory services in the most efficient or cost effective ways

-it focuses on work flow action in performing specific task, procedures, or other activities accomplished by critically reviewing each step in the process to determine where inefficiencies can be eliminated.

LEAN SYSTEM

-utilizes fewer resources, reduces costs, enhances productivity, promotes staff morale, and improves the quality of patient care

LEAN CLINICAL LABORATORY

-it is used to compare results obtained on a high and low control serum from different laboratories.

- It displays the results of the analyzers by plotting the mean values for one specimen on the ordinate (y-axis)and the other specimen on the abscissa (x-axis).

- The points falling from a center but on the 45' line suggest a proportional error, and points falling from the center but on the 45' line suggest a constant error.

YOUDEN/ TWIN PLOT

the value that occurs most frequently in a listo f items of data

MODE

difference between the highest and the lowest volume

RANGE (R)

maximum - minimum

What are 5S

(Sort. Set in Order, Shine, Standardize and Sustain),

What are PDCA

(Plan, Do, Check, and Act)

- It is the most widely used QC chart in the clinical laboratory.

SHEWHART LEVEY-JENNINGS CHART (Mean and Range Tech-nique)

• It calculates the difference between QC results and the target mean.

• Common method: V-mask, which is used instead of control limits to determine out-of-control points

• It identifies consistent bias problems; it requires computer implementation.

• This plot will give the earliest indication of systematic errors (trend) and can be used with the 1n rule.

• It is very sensitive to small, persistent errors that commonly occur in the modern, low calibration- frequency analyzer.

• Results are out of control when the slope exceeds 45' or a decision (+ 2.7 SD) is exceeded.

QUALITY CONTROL TOOLS

provide a simple, graphical view of accumulated data, including its dispersion and central tendancy. In addition to the ease with which they can be constructed, histograms provide the easiest way to evaluate the distribution of data.

HISTOGRAM

- These are expected values represented by intervals of acceptable values with upper and lower limits.

- If the expected (control) values are within the desired control limits, the clinicians are assured that the test results are accurate and precise.

-Control limits are calculated from the mean and standard deviption (SD).

- The ideal control/reference limit is between +/-2SD

- Use of a single lot for an extended period allows reliable interpretative criteria to be established which will permit efficient identification of an assay problem.

- When changing to a new lot number, laboratorians use the newly calculated mean value as the target mean but retain the previous SD value, but when more data are obtained, all values should be averaged to get the best estimates of the mean and SD.

CONTROL LIMITS (CONTROL VALUES)

-The accuracy of any assay depends on this, how they are originally constituted and how they remain stable overtime.

- General chemistry assays used 2 of control solutions, while immunoassays used 3 levels.

- To establish statistical quality control on a new instrument of on new lot numbers of control materials, the different levels of control material must be analyzed for 20 days.

-For highly precised assays (with CV less than 1%) such as blood gases, analysis for 5 days is adequate.

CONTROL SOLUTION (QC MATERIALS)

One control observation exceeds +_ 2SD

12S

WARNING

2 consecutive values exceed +_ 2SD

22S

SE

one value exceeds +_3SD

13S

RE

One value exceeds +2SD and other value exceeds -2SD

R4S

RE

4 consecutive values exceed +1SD

41S

SE

10 consecutive values fall on one side of the mean

10x

SE

SIGMA LEVEL 6

3.4 DPM

99.99966%

SIGMA LEVEL 5

230 DPM

99.977% YIELD

SIGMA LEVEL 4

6,210 DPM

99.38% YIELD

SIGMA LEVEL 3

66, 800 DPM

93.32 % YIELD

SIGMA LEVEL 2

308, 000 DPM

69.15% YIELD

SIGMA LEVEL 1

690, 000 DPM

30.85% YIELD

how blant or tall line

KURTOSIS

skewed to the right / left

SKEWNESS

graphical representation that display the control observation as a