M#17 Quality Assurance and Quality Control

62 questions • 1 y ago

Question list

Management process that focuses on the improvement of the quality of all factors that affect laboratory testing and performance. It consists of five (5) elements, what are those? QLP, QC, QA, QI, QP

Total quality management, quality laboratory process, quality control, quality assessment, quality improvement, quality planning

This is a systemic laboratory program, encompassing preanalytical, analytical, and postanalytical factors, that monitors excessive variation in specimen acceptability, test methodologies, instruments, reagents, quality control, and personnel competencies.

Quality assessment

This process is used to ensure accurate patient test results.

Quality assessment

This occurs during sample collection and transport before sample analysis and can include sample preparation and storage conditions.

Preanalytical error

This occurs during the testing process and includes problems related to reagents, instruments, controls, calibration, performance of personnel, etc.

Analytical error

This occurs after the test is performed and refers to clerical errors, reporting of results, test interpretation, etc.

Postanalytical error

Measure of a laboratory test result’s closeness to the true value.

Accuracy

It is realized when repeated laboratory results yield the same number; reproducibility.

Precision

It refers to the laboratory testing to maintain accuracy and precision over an extended period of time.

Reliability

A system used to monitor the analytical process to detect and prevent errors that would impact on the accurwcy and precision of laboratory test results; includes both _____ and _______ parameters.

Quality control, statistical, nonstatistical

Performed by laboratory personnel using control materials of known values and comparing the control values to established, acceptable ranges.

Internal QC

In Internal QC, the control material values are assessed using ______ and _______ to detect errors.

Levey-Jennings control charts, Westgard multirules

It is performed by laboratory personnel when analyzing specimens sent to the laboratory by an external agency, and the test results generated are submitted to the agency for assessment.

External QC

It is a type of assessment that is known as proficiency training.

External QC

It is required by federal regulations for all laboratories providing results for human diagnosis and/or treatment.

External QC

This determines the lowest and highest values that can be accurately measured by a particular method. This is an example of a ______ QC parameter.

Linearity check, nonstatistical

These affect precision, are unable to predict because they have no known pattern, and may alternate between a positive or negative direction.

Random errors

These are predictable and cause a constant difference in results that are consistenly positive or negative or stay the same. Such error may be due to incorrect calibration, deteriorated reagents, instrument malfunctions, etc.

Systematic erorrs

This assesses the patient’s most recent result for a particular test as compared to the patient’s previous value; the difference between the test results (delta) is calculated and compared to established limits.

Delta check

This are determined by each laboratory to fit their particular population. Intervals are generally constructed by adding and subtracting 2 standard deviations from the mean.

Reference ranges

Material of known concetration (should be traceable to NIST) that is used to calibrate an instrument or develop a standard curve.

Standard

_____ is material of known value that is analyzed with patient samples to determine acceptability of results. a. ______ _____: Values are assigned by the manufacturer. b. ______ _____: Values are determined by each individual laboratory for their methods/instruments.

Control, assayed control, unassayed control

These are statistical “rules” applied to graphical summaries of numerical quality control data to assess the acceptability of such data.

Westgard multirules

This is a data-driven, business approach to peformance improvement; it is oriented toward process identification and process improvement.

Six Σ

These are an improvement trend to make work faster by providing ways to streamline through the removal of waste.

Lean principles

_________ were established by the __________ as a series of four standards for quality management.

ISO 9000 Standards, International Organization for Standardization

Set of numbers by adding all the numbers in the set and dividing the sum by the number of values in that set.

Arithmetic mean

Middle value in a set of numbers

Median

Most frequently obtained value in a set of numbers.

Mode

Reflects the variation of data values around the mean.

Standard deviation

Reflects dispersion around the mean and is the square of the _____ _____.

Variance, standard deviation

Reflects random variation of analytical methods in units that are independent of methodology, because it is a percentage comparison of the standard deviation divided by the mean.

Coefficient of variation

Is a symmetric distribution about the mean, where ____% of th valeus lie within +-2 s an approximately _% will normally fall outside.

Normal distribution, 95.45, 5

The ____ of a test is the percentage of individuals with a specific disease that are correctly identifid or predicted by the test as having the disease.

Sensitivity

The ____ of a test is the percentage of individuals without the specific disease that are correctly identified or predicted by the test as not having the disease.

Specificity

_____ of a test utilizes the parameters of test sensitivity and specificity as well as disease prevalance.

Predicted value

The percentage of people with positive test resukts who have the disease.

Positive predicted value

Percentage of people with negative test results who do not have the disease.

Negative predicted value

These are calculated for each laboratory’s menu of tests. Each laboratory serves a unique population, so this must be determine for that population.

Reference intervals

Reference intervals use a minimum of __ specimens from “healthy” people to determine analyte values, calculate the mean and standard deviation, and compare to the reference interval suggested by the manufacturer.

In reference intervals, it is prefrered that analyte values should be determined using a minimum or __ specimens from healthy people in each relevant sex and age category.

120

It is a comprehensive program involving statistical analysis of control materials, which are analyzed with a batch of patient samples to determine acceptability of the run.

Internal quality control

In Internal quality control, this is commercially manufactured lyophilized or liquis materials that have the same matrix as patient specimens and are used to evalaute the test process.

Control material

These are selected so that values will be at medically significant levels.

Control materials

In control material, it is preffered that the same lot number of control material be purchased and used for at least a _-year period.

This must be accurately reconstituted according to the manufacturwr’s directions to avoid vial-to-vial variability. The stability of the reconstituted material is important.

Lyophilized control material

This use materials that will provide both negative and positive results.

Qualitative controls

This is constructed monthly for each control material using the mean +-3 standard deviations to construct a graph that allows visual detection of shifts and trends. The control value is ploted versus the established range, with the acceptable control range represented by +-2 standard deviations.

Levey-Jennings control chart

It is a gradual change in the mean that is reflected as either as a decrease or increase of consecutive control values. The change occurs only in ___ direction.

Trend, one

It is a sudden change in the mean that is reflected as consecutive control values above or below the mean.

Shift

It is a control procedure that utilizes control rules to assess numerical quality control data; the control rules establish the limits for data rejection in a system with two controls. Other rules apply when three controls are used.

Westgard multirules

1 control value exceeds the mean +-2 standard deviations.

12s

1 control value exceeds the mean +-2 standard deviations.

13s

2 consecutive control values exceed the same 2 standard deviation 0 limit.

22s

Westgard rule where results are reportable

12s

Westgard rules responsible for detecting random error (2)

13s, R4s

1 control value in q group exceeds the mean +2s and a second control value exceeds the mean -2s, creating a _ standard deviation spread.

R4s, 4

4 consecutive control values are recorded on one side of the mean and exceed either the same mean of +1s or the same mean -1s.

41s

10 consecutive control values are recorded on one side of the mean, either above or below the mean.

10x

Westgard rule responsible for detecting systematic error.

41s, 10x

A graphical technique for analyzing interlaboratory data when each laboratory has made two runs on the same analyte or one run on two different analytes. The plot identifies within-laboratory and between-laboratory variability.

Youden plot

It refers to a program where a clinical laboratory contracts with an agency to receive and assay samples, the concentration of which is unknown to the participating clinical laboratory.

External quality control

Medical Terminology (Abbreviations)

Anonymous · 19 questions · 1 y ago

Medical Terminology (Abbreviations)