Week 08: Quality Management in Labs
45 Questions
2 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

When should you reject consecutive control measurements based on the +3SD rule?

  • When the mean is above +1SD
  • When 10 measurements exceed both mean plus 2s and mean minus 2s
  • When 10 consecutive control measurements fall on one side of the mean (correct)
  • When 10 consecutive measurements are below the mean

    • What does the '2 of 32s' rule indicate?

  • Accept all measurements that are within two standard deviations
  • Reject only if all three measurements are above the mean
  • Reject when 2 out of 3 measurements exceed the mean plus 2s or fall below the mean minus 2s (correct)
  • Reject if 2 out of 3 measurements fall outside the mean range

    • Under the '7 T' rule, when should you reject the measurements?

  • When seven measurements are all below the mean
  • When seven measurements trend in alternating directions
  • When seven control measurements trend in the same direction (correct)
  • When seven consecutive measurements exceed the mean plus 3s

    • What is the significance of the term 'Shift' in control measurement?

    <p>Indicates a change in the mean value</p> Signup and view all the answers

    What is implied if the control measurements are consistently trending lower than the mean?

    <p>There may be an issue that requires investigating</p> Signup and view all the answers

    What does a control value exceeding x ± 2s signify in the Westgard multi-rule control chart?

    <p>Warning for careful inspection</p> Signup and view all the answers

    What is indicated by two consecutive control values exceeding x ± 2s?

    <p>Systematic rejection of results</p> Signup and view all the answers

    What is one primary objective of using control material in the clinical laboratory?

    <p>To ensure accurate measurements</p> Signup and view all the answers

    Which factor is considered a biological influence on specimen analysis?

    <p>Sex</p> Signup and view all the answers

    What causes imprecision in quality control charts?

    <p>Operator inattention</p> Signup and view all the answers

    What does a trend in a control chart typically indicate?

    <p>Deterioration in reagents and standards</p> Signup and view all the answers

    What is a primary use of Levey-Jennings control charts in clinical laboratories?

    <p>To monitor performance of analytical methods</p> Signup and view all the answers

    Which of the following is NOT a requirement for quality control material?

    <p>Accessible only for short periods</p> Signup and view all the answers

    Which of the following is NOT part of the Westgard Multi-Rule control chart?

    <p>31s rule</p> Signup and view all the answers

    What does the 10x rule in the Westgard chart indicate?

    <p>Ten consecutive values falling on the same side of x</p> Signup and view all the answers

    Which of these is a component of control limits in laboratory settings?

    <p>Standard deviation based on historical data</p> Signup and view all the answers

    What is the primary function of the Westgard multi-rules in laboratory control data interpretation?

    <p>To interpret and assess quality control results</p> Signup and view all the answers

    What is the implication of a shift in quality control charts?

    <p>Introduction of something new in the assay procedure</p> Signup and view all the answers

    What is the effect of altitude on specimen analysis?

    <p>It alters the chemical composition of specimens.</p> Signup and view all the answers

    What is true acceptance of results in a control chart?

    <p>Accepting results that are statistically sound</p> Signup and view all the answers

    In the context of reliable analytical methods, which process is NOT part of achieving reliability?

    <p>Selectivity</p> Signup and view all the answers

    Which of the following best describes the purpose of Total Quality Management (TQM) in a clinical laboratory?

    <p>To ensure accurate patient diagnoses through comprehensive quality systems</p> Signup and view all the answers

    What is required for proper patient identification in the pre-analytical phase?

    <p>Two identifiers, such as name and identification number</p> Signup and view all the answers

    What is the purpose of defining turnaround time (TAT) for laboratory tests?

    <p>To track the efficiency of specimen collection and reporting</p> Signup and view all the answers

    Which of the following factors can affect laboratory test results during the pre-analytical phase?

    <p>Recent food, alcohol, or drug intake by the patient</p> Signup and view all the answers

    What aspect of quality control involves monitoring specimen and patient identification?

    <p>Quality Assessment</p> Signup and view all the answers

    Which of the following is NOT a part of controlling analytical variables?

    <p>Patient compliance with pre-test instructions</p> Signup and view all the answers

    What is the significance of using a laboratory log for specimen and request tracking?

    <p>It helps prevent transcription errors and matching issues</p> Signup and view all the answers

    Which step is critical in ensuring accurate specimen collection?

    <p>Using preservatives and proper containers</p> Signup and view all the answers

    What is the primary purpose of using control materials in testing?

    <p>To validate the reliability of the test system.</p> Signup and view all the answers

    Which of the following accurately describes calibrators?

    <p>Substances with an established concentration used to set measuring points.</p> Signup and view all the answers

    What is an important characteristic of internal quality control (IQC)?

    <p>It ensures reliable results during all phases of testing.</p> Signup and view all the answers

    What distinguishes 'assayed' control material from 'unassayed' control material?

    <p>Assayed materials have a target value predetermined, unlike unassayed materials.</p> Signup and view all the answers

    What does external quality assessment (EQA) primarily involve?

    <p>Organized inter-laboratory comparison to enhance performance.</p> Signup and view all the answers

    How frequently should control material be run according to the guidelines?

    <p>Periodically during testing to ensure reliability.</p> Signup and view all the answers

    What is required for 'in-house' pooled sera before use?

    <p>Full assay and validation.</p> Signup and view all the answers

    What is the initial step in implementing quantitative quality control (QC)?

    <p>Obtain control material.</p> Signup and view all the answers

    When should a run be rejected according to the +3SD rule?

    <p>When a single control measurement exceeds the mean plus 3s</p> Signup and view all the answers

    Under the 22s rule, when is a run rejected?

    <p>When two consecutive control measurements exceed the mean plus 2s</p> Signup and view all the answers

    According to the R4s rule, what condition warrants a rejection?

    <p>When one measurement exceeds the mean plus 2s and another exceeds the mean minus 2s</p> Signup and view all the answers

    What is the rejection criterion for the 4 1s rule?

    <p>Reject when 4 consecutive control measurements exceed the same mean plus 1s or mean minus 1s</p> Signup and view all the answers

    What does the term 'control limit' refer to?

    <p>The boundaries in a control chart determined by mean plus and minus values</p> Signup and view all the answers

    What is meant by 'consecutive control measurements'?

    <p>Measurements taken in a specific sequence with no gaps in between</p> Signup and view all the answers

    Which of the following statements about the rules is true?

    <p>The 4 1s rule requires four consecutive measurements for rejection</p> Signup and view all the answers

    How do the SD values relate to the rejection criteria?

    <p>Rejection criteria are based on exceeding a number of SDs from the mean</p> Signup and view all the answers

    Study Notes

    Week 08: Quality Management

    • This week's topic is Quality Management in the clinical laboratory.
    • Key objectives:
      • Describe quality control systems and validation methods in the lab.
      • Detail lab testing processes and potential errors.
      • Explain pre-analytical, analytical, and post-analytical variables and their effects on results.
      • Detail how to control pre-analytical, analytical, and post analytical variables.

    Total Quality Management

    • Total quality management (TQM) aims to improve the clinical lab.
    • TQM focuses on controlling pre-analytical and analytical variables.
    • External quality assessment and proficiency testing programs are essential components of TQM.
    • Early problem detection prevents further issues.

    Quality Management Cycle

    • A cyclical process for quality management in the lab.
    • Key components are: quality planning, quality improvement, quality laboratory process, quality assessment, and quality control.

    Implementing Total Quality Management (TQM)

    • PDCA (Plan-Do-Check-Act) cycle is fundamental to TQM implementation.
    • Analytical processes, policies, practices, and work procedures are crucial for quality.
    • Statistical and non-statistical control procedures (linearity checks, reagent and standard checks, and temperature monitoring) ensure quality.

    Pre-analytical Variables Control

    • Patient Identification: Correct patient and specimen identification is critical (at least 2 identifiers).
    • Turn around time (TAT): Lab tests must be completed in an efficient manner. Accurate time recording, clear definitions for each test type and monitoring are vital. Specimen receipt in the lab, specimen collection, and test result reporting must be clearly defined.
    • Laboratory Log (Specimen + Request): A log must be used for each specimen and request, with clear record-keeping, and accurate patient identification. Transcription errors can be a problem, especially with manual data entry.
    • Patient Preparation: Patient factors that impact tests (recent intake of food, alcohol, or drugs, smoking, exercise, stress, sleep). Instructions and procedures should be clear.

    Control of Pre-Analytical Variables (Continued)

    • Specimen Collection: Proper handling procedures for specimens need to be in place, especially regarding preservatives and containers. Aliquot distribution is also important.
    • Specimen Separation and Distribution: Use of centrifuges and appropriate containers.
    • Specimen Transport: Transporting specimens appropriately (cooled, frozen, protected from light).

    Non-controllable Variables

    • Factors outside the lab’s control, including biological influences (age, sex, underlying medical conditions) and environmental factors (altitude, ambient temperature, geographic location, seasonal influence).

    Week 09-10: Control of Analytical Variables

    • Objectives:
      • Compare internal & external quality assessment programs
      • Understand the need for control material in clinical labs
      • Explain the use of control charts
      • Describe control limits calculation
      • Assess Levey-Jennings control charts and identify errors
      • Understand Westgard multirules for data interpretation

    Control of Analytical Phase

    • Employ validated analytical methods for lab testing.
    • Calibration of analytical procedures is essential.
    • Use quality control material specific to the assay.
    • Monitor performance using Levey-Jennings charts.
    • Apply Westgard multirules to interpret data.

    Control of Analytical Variables (Continued)

    • Ensure correct measurements through accurate methods.
    • Key steps for reliable analytical procedures: selection, evaluation, implementation, maintenance, and control.

    Control Material

    • Control materials mimic patient sample characteristics.
    • They should be stable and have clear composition.
    • Control materials are used for a significant duration for precise control.
    • Distinction between assayed (pre-determined target value) and unassayed (no pre-determined target value) control materials
    • "In-house" pooled sera requires full validation.

    Components of Quality Assurance

    • Internal Quality Control (IQC): Lab professionals take steps to generate reliable results.

      • Focuses on the pre-analytical, analytical, and post-analytical phases.

    • External Quality Assessment (EQA): A tool to assess IQC performance (inter-lab comparison).

    Steps in Implementing Quantitative QC

    • Obtain control material.
    • Run each control 20 times over 30 days.
    • Calculate the mean and +/- 1, 2, and 3 Standard Deviations (SD) from the data.

    Measurement Procedure

    • Determines quantity values.
    • Includes measurement errors (difference between obtained and true value).
    • Measurement errors have two components: random and systematic.

    Random Errors

    • Unpredictable analytical variations influence measurements.
    • Possible causes: wrong pipetting techniques, inconsistent reactions timing/temperature, instability of instruments.

    Systematic Errors

    • Errors that affect measurements consistently.
    • Possible causes: errors in calibrator values, degradation of calibration materials, incorrect reagent/sample volumes, improper reaction times/temperatures, incorrect instrument settings, calculation errors, and interference in samples.

    QC Charts and Rules

    • Levey-Jennings charts are critical for analyzing QC data.
    • QC charts should include test name, date, source of control, and statistical data.
    • Charts help identify analysis errors and prevent reporting of incorrect data.

    Westgard Multirule Chart

    • Use two control specimens in each analytical run (one normal, one abnormal) and plot them on the chart along with other data.
    • Specific rules (12s, 13s, 22s, R4s, 41s, 10x) help in interpreting data and detecting and preventing errors.

    Examining QC Charts

    • Imprecision: Inconsistency in measurements, often due to operator error (e.g., pipette variability, lack of attention to detail).
    • Inaccuracy: Errors in measurements, resulting in inaccurate data. Possible causes include reagents/standards degrading, instrument deterioration, introducing new procedures/new lots.
    • Trends/Shifts: Changes in the results over time (e.g., a gradual increase or decrease in readings), which could point to issues needing investigation.

    Control (Levey-Jennings) Chart Interpretation

    • Continuous evaluation of control values.
    • Interpretation of analysis results (acceptance or rejection based on different criteria).

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Week 8, 9, & 10 Clinical Chemistry I PDF

    Description

    This quiz covers essential concepts of Quality Management within the clinical laboratory setting. Topics include quality control systems, lab testing processes, TQM principles, and the quality management cycle. Understand the importance of managing pre-analytical, analytical, and post-analytical variables.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser