In your routine laboratory works, do you have to issue a statement of conformity after testing a product sample, such as stating a Pass or fail, a compliance or non-compliance? What is your decision rule as required by this ISO standard? What is the risk to make a wrong decision in rejecting the test result based on the product specification limit when it is actually in conformance? Are you able to control such a risk in order to make an informed decision?
If you have all these questions in mind, I have got the answers for you.
Decision rule = “Rule that describe how measurement uncertainty is accounted for when stating conformity with a specified requirement
Decision rule and conformity testing
Statements of Conformity and Decision Rules
Statements of conformity and decision rulesMaryam Sourani
The document provides guidance on statements of conformity and decision rules as required by ISO/IEC 17025:2017. It defines statements of conformity and the three common types: compliance, non-compliance, and indeterminate. It explains how to determine conformity by evaluating if the measurement result plus or minus the uncertainty is within, exceeds, or overlaps the specification limits. It also summarizes the key ISO requirements related to statements of conformity and how laboratories can meet them, such as documenting decision rules and ensuring statements are relevant.
This document discusses quality assurance and quality control procedures for chemical test laboratories to meet ISO/IEC 17025:2017 requirements. It covers establishing quality assurance plans, differentiating quality assurance and quality control, applying quality control practices like blanks, replicates, and laboratory controls. Quality control charts are presented as a tool to monitor analytical accuracy and precision over time.
The overall meaning of metrological traceability (Calibration Traceability ch...Ahmed R. Sayed
This Slide talks about the meteorological Traceability
Important Content For Calibration and testing
this slide contain information for Traceability Chain & Traceability Pyramid and Calibration Management Requirement
Paper Presnetation on ISO/IEC 17025:2017 organized at Labtech2017 in Bahrain. The topics discussed in that presentation like what are the major changes, what is considered in revised ISO 17025:2017, requirements of ISO 17025:2017, etc. are explained in this ppt presentation.
This publication describes list of all ISO 17025:2017 Documents that covers all the requirements of upgraded standard and used them for ISO/IEC 17025:2017 re-accreditation. ISO 17025:2017 required documents such as manual, procedures, audit checklist listed in this PDF.
Decision rule = “Rule that describe how measurement uncertainty is accounted for when stating conformity with a specified requirement
Decision rule and conformity testing
Statements of Conformity and Decision Rules
Statements of conformity and decision rulesMaryam Sourani
The document provides guidance on statements of conformity and decision rules as required by ISO/IEC 17025:2017. It defines statements of conformity and the three common types: compliance, non-compliance, and indeterminate. It explains how to determine conformity by evaluating if the measurement result plus or minus the uncertainty is within, exceeds, or overlaps the specification limits. It also summarizes the key ISO requirements related to statements of conformity and how laboratories can meet them, such as documenting decision rules and ensuring statements are relevant.
This document discusses quality assurance and quality control procedures for chemical test laboratories to meet ISO/IEC 17025:2017 requirements. It covers establishing quality assurance plans, differentiating quality assurance and quality control, applying quality control practices like blanks, replicates, and laboratory controls. Quality control charts are presented as a tool to monitor analytical accuracy and precision over time.
The overall meaning of metrological traceability (Calibration Traceability ch...Ahmed R. Sayed
This Slide talks about the meteorological Traceability
Important Content For Calibration and testing
this slide contain information for Traceability Chain & Traceability Pyramid and Calibration Management Requirement
Paper Presnetation on ISO/IEC 17025:2017 organized at Labtech2017 in Bahrain. The topics discussed in that presentation like what are the major changes, what is considered in revised ISO 17025:2017, requirements of ISO 17025:2017, etc. are explained in this ppt presentation.
This publication describes list of all ISO 17025:2017 Documents that covers all the requirements of upgraded standard and used them for ISO/IEC 17025:2017 re-accreditation. ISO 17025:2017 required documents such as manual, procedures, audit checklist listed in this PDF.
ISO/IEC 17025 outlines the requirements for laboratories to demonstrate competence and generate reliable test and calibration results. It covers management requirements like documentation, audits, and reviews as well as technical requirements for personnel, methods, equipment, measurement traceability and reporting. The standard requires laboratories to have a quality management system in place to ensure consistent, valid results and provide traceable measurements that can be compared internationally through an unbroken chain of calibrations.
Estimation of Measurement Uncertainty in Labs: a requirement for ISO 17025 Ac...PECB
Knowledge of the uncertainty of measurement of testing and calibration results is fundamentally important for laboratories, their clients and all institutions using these results for comparative purposes. Uncertainty of measurement is a very important metric of the quality of a result or a testing method.
Main points covered:
• To introduce the basic concepts related to measurement results and measurement uncertainty
• Explain the relevance of these concepts to chemical analysis data
• Introduce mathematical concepts, uncertainty sources and important approaches for estimation of measurement uncertainty
Presenter:
This webinar was presented by Dotun Bolade, who is an Analytical Chemist/Environmental Scientist by training and practice with years of experience in laboratory instrumentation and automation. For him, ISO management systems have become second nature having worked in environments where ISO 9001, 14001, 18001 and 17025 have been fully implemented. He is a Certified PECB ISO/IEC 17025 Lead Assessor.
Link of the recorded session published on YouTube: https://youtu.be/AOpFou7_FVI
This document is an ISO/IEC 17025:2017 audit checklist for laboratories. It contains requirements for laboratories to meet the standard in areas such as impartiality, confidentiality, organizational structure, personnel, facilities, equipment, metrological traceability, and externally provided products and services. The checklist provides the requirement, reference, status of implementation, and a comment section for each clause to help laboratories evaluate their conformance to the standard.
This document outlines the policy and procedure for method verification at Presbyterian Laboratory Services. It defines key terms and describes the process for selecting, approving, and verifying new testing methods before reporting patient results. The verification process involves evaluating a method's precision, accuracy, linearity, reference range, and potential for carryover through statistical analysis of test results using quality controls, patient samples, and known standards. The goal is to ensure new methods meet performance standards before clinical use.
ISO 17025 is an international standard for testing and calibration laboratories seeking accreditation. It has requirements for management, technical operations, and quality assurance. Accreditation increases confidence in test results, enhances customer satisfaction, and improves laboratory effectiveness through regular inspections. While accreditation requires costs for implementation and maintenance, it also provides benefits like reduced re-testing and an improved reputation. The standard has been adopted by accreditation bodies in several countries including Australia, New Zealand, and India.
The document summarizes the key changes and structure of ISO/IEC 17025:2017 compared to the 2005 version. Major changes include an expanded scope to include sampling and a process-based approach. It adopts a new high level structure with common clauses across standards. Key requirements include impartiality, confidentiality, personnel competence, facilities, equipment calibration, metrological traceability, and management of externally provided products and services. The standard aims to ensure laboratories consistently operate at a high level of technical competence and quality.
This document outlines the documentation requirements for laboratories to be compliant with ISO/IEC-17025:2017. It lists the key clauses of the standard and whether each technical requirement is procedures (P), documented (R) or implemented (O). Some of the main requirements covered include having documented procedures for impartiality, confidentiality, handling complaints and nonconforming work. Laboratories must also document their organizational structure, personnel requirements, equipment management and methods validation. Technical records must contain sufficient information to enable repetition of tests and monitoring is required to ensure validity of results.
Decision rule construction requires four components: the measurement result, its measurement uncertainty, the specification limit or limits, and the acceptable level of the probability of making each type of wrong decision
ISO 17025 certification gives testing and calibration laboratories the same type of accreditation that ISO 9001 gives to manufacturing and service organizations. Learn more at http://www.CEBOS.com
This document provides an overview of recent developments in top-down approaches for evaluating measurement uncertainty in testing laboratories. It discusses the strengths and weaknesses of the traditional bottom-up GUM method and introduces several top-down methods including those based on precision, accuracy and trueness using quality control data; control chart methods; the use of validation data and reference materials; and experience-based models like Horwitz's equation. The document provides details on how measurement uncertainty is estimated using these various top-down approaches.
The document discusses the process for updating an existing ISO/IEC 17025:2005 accredited laboratory management system to comply with the revised ISO/IEC 17025:2017 standard. It outlines 8 key steps, including conducting awareness training on the revisions, reviewing and revising documentation, implementing risk-based thinking, training auditors, conducting internal audits, addressing nonconformities, applying for an updated accreditation certificate, and undergoing a final assessment audit. Accredited laboratories must complete the upgrade process within 3 years of the 2017 standard's release.
ISO 17025 Accreditation Detail Review Abdul Rahman
In this presentation, you would get knowledge about ISO17025. It's an updated version, terms and definitions. Which documents are required for certification.
This document discusses measurement uncertainty. It defines measurement uncertainty as a parameter included with any measurement result that accounts for possible errors. It describes sources of uncertainty like sampling, storage conditions, and personal effects. The document outlines methods of calculating uncertainty using the standard deviation, and explains why assessing uncertainty is important for interpreting results and ensuring measurement quality. Measurement uncertainty is a key component of any measurement result.
This document provides an introduction to uncertainty measurements. It explains that there is always uncertainty involved when taking measurements as values can vary depending on factors like how, when and where something is measured. It describes the two main sources of uncertainty as random errors which are unpredictable, and systematic errors which are constant. The document then outlines the process for calculating uncertainty which involves taking multiple readings to determine standard deviation and uncertainty (Type A), and combining various uncertainty components from calibration certificates and manufacturers alongside sensitivity coefficients to determine combined and expanded uncertainty using a normal distribution with 95% confidence (Type B). It emphasizes that the process is the same for measurements in decibels or real numbers but the calculations are different.
Quality objectives are specific, measurable targets set by an organization to demonstrate the effectiveness of its quality management system and progress towards its quality policy. Examples of quality objectives include reducing defect and scrap rates, customer complaints, and non-conformances found in internal audits. Objectives should be established for all levels and functions, measured regularly, and not created solely for certification without aiming to improve the quality system.
The document discusses the requirements of ISO/IEC 17025, the standard that specifies the general requirements for the competence of testing and calibration laboratories. It covers the management system requirements including documents and records control, customer service, audits and reviews. The technical requirements include personnel, test methods, equipment, measurement traceability and reporting of results. The standard aims to ensure laboratories produce precise and accurate test and calibration data.
This document discusses various concepts related to analytical method validation including accuracy, precision, specificity, detection limit, and quantitation limit. It provides definitions and recommendations for determining each concept. For accuracy, it recommends assessing using spiked samples or an independent procedure and reporting as percent recovery. For precision, it recommends determining repeatability using 9 determinations at 3 concentrations and reporting as standard deviation and coefficient of variation. Detection limit can be determined visually, by signal-to-noise ratio, or by standard deviation of the blank. Quantitation limit is the lowest concentration that can be quantified and can also be determined visually or by signal-to-noise ratio.
What Documentation Required for ISO 17025:2017 Accreditation?Global Manager Group
Global Manager Group has prepared presentation to provide information about Calibration and Testing Laboratory Accreditation Standard - ISO 17025 and about Documentation Requirements. All the documents like quality manual, procedures, audit checklist, etc that required for the ISO 17025:2017 Accreditation process are described in details in this presentation.
The document discusses differences between ISO Guide 25 and ISO/IEC 17025 standards for testing and calibration laboratories. Key differences include ISO 17025 having more detailed requirements for management systems, documentation control, purchasing, nonconforming work handling, corrective and preventive action, and technical requirements. Accreditation bodies will transition from Guide 25 to mandatory ISO 17025 accreditation over the next two years.
Key factors and main change over in iso 17025 2017Dr.Lenin raja
1. The document discusses changes to ISO 17025:2017 regarding general requirements for testing and calibration laboratories. It outlines key changes to requirements regarding impartiality, confidentiality, organizational structure, personnel competence, equipment, metrological traceability, externally provided products/services, and method selection/validation.
2. New standards specify that laboratories must be committed to impartiality and minimize risks to impartiality. Personnel must keep information confidential, unless legally required. Laboratories must define their organizational structure and personnel responsibilities.
3. Equipment must be suitable for intended measurements and calibrated when it impacts validity or traceability of results. Laboratories must establish traceability of measurements to SI units through an unbroken chain of calibrations.
This document discusses the requirements in ISO/IEC 17025:2017 for including decision rules when reporting statements of conformity. It states that decision rules must account for measurement uncertainty and the risk of false acceptance/rejection. Examples of common decision rules are provided that take uncertainty into account, such as only stating conformity if the measurement result plus uncertainty is fully within specification limits. Guidance is given on documenting decision rules and obtaining customer agreement prior to testing.
Basic QC Statistics - Improving Laboratory Performance Through Quality Contro...Randox
Randox Quality Control's latest educational guide examines Internal Quality Control, External Quality Assessment, Why laboratories should run QC, How often laboratories should run QC, Basic QC statistics and the quality control process.
ISO/IEC 17025 outlines the requirements for laboratories to demonstrate competence and generate reliable test and calibration results. It covers management requirements like documentation, audits, and reviews as well as technical requirements for personnel, methods, equipment, measurement traceability and reporting. The standard requires laboratories to have a quality management system in place to ensure consistent, valid results and provide traceable measurements that can be compared internationally through an unbroken chain of calibrations.
Estimation of Measurement Uncertainty in Labs: a requirement for ISO 17025 Ac...PECB
Knowledge of the uncertainty of measurement of testing and calibration results is fundamentally important for laboratories, their clients and all institutions using these results for comparative purposes. Uncertainty of measurement is a very important metric of the quality of a result or a testing method.
Main points covered:
• To introduce the basic concepts related to measurement results and measurement uncertainty
• Explain the relevance of these concepts to chemical analysis data
• Introduce mathematical concepts, uncertainty sources and important approaches for estimation of measurement uncertainty
Presenter:
This webinar was presented by Dotun Bolade, who is an Analytical Chemist/Environmental Scientist by training and practice with years of experience in laboratory instrumentation and automation. For him, ISO management systems have become second nature having worked in environments where ISO 9001, 14001, 18001 and 17025 have been fully implemented. He is a Certified PECB ISO/IEC 17025 Lead Assessor.
Link of the recorded session published on YouTube: https://youtu.be/AOpFou7_FVI
This document is an ISO/IEC 17025:2017 audit checklist for laboratories. It contains requirements for laboratories to meet the standard in areas such as impartiality, confidentiality, organizational structure, personnel, facilities, equipment, metrological traceability, and externally provided products and services. The checklist provides the requirement, reference, status of implementation, and a comment section for each clause to help laboratories evaluate their conformance to the standard.
This document outlines the policy and procedure for method verification at Presbyterian Laboratory Services. It defines key terms and describes the process for selecting, approving, and verifying new testing methods before reporting patient results. The verification process involves evaluating a method's precision, accuracy, linearity, reference range, and potential for carryover through statistical analysis of test results using quality controls, patient samples, and known standards. The goal is to ensure new methods meet performance standards before clinical use.
ISO 17025 is an international standard for testing and calibration laboratories seeking accreditation. It has requirements for management, technical operations, and quality assurance. Accreditation increases confidence in test results, enhances customer satisfaction, and improves laboratory effectiveness through regular inspections. While accreditation requires costs for implementation and maintenance, it also provides benefits like reduced re-testing and an improved reputation. The standard has been adopted by accreditation bodies in several countries including Australia, New Zealand, and India.
The document summarizes the key changes and structure of ISO/IEC 17025:2017 compared to the 2005 version. Major changes include an expanded scope to include sampling and a process-based approach. It adopts a new high level structure with common clauses across standards. Key requirements include impartiality, confidentiality, personnel competence, facilities, equipment calibration, metrological traceability, and management of externally provided products and services. The standard aims to ensure laboratories consistently operate at a high level of technical competence and quality.
This document outlines the documentation requirements for laboratories to be compliant with ISO/IEC-17025:2017. It lists the key clauses of the standard and whether each technical requirement is procedures (P), documented (R) or implemented (O). Some of the main requirements covered include having documented procedures for impartiality, confidentiality, handling complaints and nonconforming work. Laboratories must also document their organizational structure, personnel requirements, equipment management and methods validation. Technical records must contain sufficient information to enable repetition of tests and monitoring is required to ensure validity of results.
Decision rule construction requires four components: the measurement result, its measurement uncertainty, the specification limit or limits, and the acceptable level of the probability of making each type of wrong decision
ISO 17025 certification gives testing and calibration laboratories the same type of accreditation that ISO 9001 gives to manufacturing and service organizations. Learn more at http://www.CEBOS.com
This document provides an overview of recent developments in top-down approaches for evaluating measurement uncertainty in testing laboratories. It discusses the strengths and weaknesses of the traditional bottom-up GUM method and introduces several top-down methods including those based on precision, accuracy and trueness using quality control data; control chart methods; the use of validation data and reference materials; and experience-based models like Horwitz's equation. The document provides details on how measurement uncertainty is estimated using these various top-down approaches.
The document discusses the process for updating an existing ISO/IEC 17025:2005 accredited laboratory management system to comply with the revised ISO/IEC 17025:2017 standard. It outlines 8 key steps, including conducting awareness training on the revisions, reviewing and revising documentation, implementing risk-based thinking, training auditors, conducting internal audits, addressing nonconformities, applying for an updated accreditation certificate, and undergoing a final assessment audit. Accredited laboratories must complete the upgrade process within 3 years of the 2017 standard's release.
ISO 17025 Accreditation Detail Review Abdul Rahman
In this presentation, you would get knowledge about ISO17025. It's an updated version, terms and definitions. Which documents are required for certification.
This document discusses measurement uncertainty. It defines measurement uncertainty as a parameter included with any measurement result that accounts for possible errors. It describes sources of uncertainty like sampling, storage conditions, and personal effects. The document outlines methods of calculating uncertainty using the standard deviation, and explains why assessing uncertainty is important for interpreting results and ensuring measurement quality. Measurement uncertainty is a key component of any measurement result.
This document provides an introduction to uncertainty measurements. It explains that there is always uncertainty involved when taking measurements as values can vary depending on factors like how, when and where something is measured. It describes the two main sources of uncertainty as random errors which are unpredictable, and systematic errors which are constant. The document then outlines the process for calculating uncertainty which involves taking multiple readings to determine standard deviation and uncertainty (Type A), and combining various uncertainty components from calibration certificates and manufacturers alongside sensitivity coefficients to determine combined and expanded uncertainty using a normal distribution with 95% confidence (Type B). It emphasizes that the process is the same for measurements in decibels or real numbers but the calculations are different.
Quality objectives are specific, measurable targets set by an organization to demonstrate the effectiveness of its quality management system and progress towards its quality policy. Examples of quality objectives include reducing defect and scrap rates, customer complaints, and non-conformances found in internal audits. Objectives should be established for all levels and functions, measured regularly, and not created solely for certification without aiming to improve the quality system.
The document discusses the requirements of ISO/IEC 17025, the standard that specifies the general requirements for the competence of testing and calibration laboratories. It covers the management system requirements including documents and records control, customer service, audits and reviews. The technical requirements include personnel, test methods, equipment, measurement traceability and reporting of results. The standard aims to ensure laboratories produce precise and accurate test and calibration data.
This document discusses various concepts related to analytical method validation including accuracy, precision, specificity, detection limit, and quantitation limit. It provides definitions and recommendations for determining each concept. For accuracy, it recommends assessing using spiked samples or an independent procedure and reporting as percent recovery. For precision, it recommends determining repeatability using 9 determinations at 3 concentrations and reporting as standard deviation and coefficient of variation. Detection limit can be determined visually, by signal-to-noise ratio, or by standard deviation of the blank. Quantitation limit is the lowest concentration that can be quantified and can also be determined visually or by signal-to-noise ratio.
What Documentation Required for ISO 17025:2017 Accreditation?Global Manager Group
Global Manager Group has prepared presentation to provide information about Calibration and Testing Laboratory Accreditation Standard - ISO 17025 and about Documentation Requirements. All the documents like quality manual, procedures, audit checklist, etc that required for the ISO 17025:2017 Accreditation process are described in details in this presentation.
The document discusses differences between ISO Guide 25 and ISO/IEC 17025 standards for testing and calibration laboratories. Key differences include ISO 17025 having more detailed requirements for management systems, documentation control, purchasing, nonconforming work handling, corrective and preventive action, and technical requirements. Accreditation bodies will transition from Guide 25 to mandatory ISO 17025 accreditation over the next two years.
Key factors and main change over in iso 17025 2017Dr.Lenin raja
1. The document discusses changes to ISO 17025:2017 regarding general requirements for testing and calibration laboratories. It outlines key changes to requirements regarding impartiality, confidentiality, organizational structure, personnel competence, equipment, metrological traceability, externally provided products/services, and method selection/validation.
2. New standards specify that laboratories must be committed to impartiality and minimize risks to impartiality. Personnel must keep information confidential, unless legally required. Laboratories must define their organizational structure and personnel responsibilities.
3. Equipment must be suitable for intended measurements and calibrated when it impacts validity or traceability of results. Laboratories must establish traceability of measurements to SI units through an unbroken chain of calibrations.
This document discusses the requirements in ISO/IEC 17025:2017 for including decision rules when reporting statements of conformity. It states that decision rules must account for measurement uncertainty and the risk of false acceptance/rejection. Examples of common decision rules are provided that take uncertainty into account, such as only stating conformity if the measurement result plus uncertainty is fully within specification limits. Guidance is given on documenting decision rules and obtaining customer agreement prior to testing.
Basic QC Statistics - Improving Laboratory Performance Through Quality Contro...Randox
Randox Quality Control's latest educational guide examines Internal Quality Control, External Quality Assessment, Why laboratories should run QC, How often laboratories should run QC, Basic QC statistics and the quality control process.
The laboratory shall determine measurement uncertainty for each measurement procedure,
in the examination phases used to report measured quantity values on patients’ samples. The
laboratory shall define the performance requirements for the measurement uncertainty of each
measurement procedure and regularly review estimates of measurement uncertainty.
In this comprehensive presentation, there is detailed critical aspects of ensuring compliance with Measurement Uncertainty (MU) requirements outlined in the ISO 15189:2012 standard. Focused on laboratories in the CAP Laboratory Accreditation Program, the guidance explores ongoing routines such as Quality Control, Proficiency testing, Calibration, Multi-instrument comparison, Method comparison, and Data generation supporting analytical measurement range. The presentation provides clarity on the determination of MU for each measurement procedure and recommends practices for accessing confidence levels. Exclusions, key definitions, and a practical example of MU are highlighted, along with a comparison of Accuracy vs. Precision. This informative session aims to equip medical professionals with a nuanced understanding of MU for robust quality assurance
Acceptance sampling is a quality control technique where a random sample is taken from a lot and used to determine whether to accept or reject the entire lot. It aims to inspect a portion of items to draw a conclusion about the quality of the whole lot in a cost-effective manner. Key aspects include defining acceptance quality limits, sampling risks, developing sampling plans involving sample size and acceptance/rejection criteria, and understanding operating characteristic curves showing the probability of acceptance at different quality levels. The technique helps improve overall quality while reducing inspection costs and risks compared to 100% inspection.
This document outlines the key steps in method validation for clinical chemistry laboratories. It defines method validation and discusses when methods should be validated. The key aspects that must be validated include calibration, precision, accuracy, linearity, limit of detection, analytical range, sensitivity, specificity, ruggedness and robustness. Thorough documentation of the validation study is also required. Validating a method involves experimentally testing these parameters and documenting the results to provide objective evidence that the method is suitable for its intended use.
This document summarizes strategies for mitigating risk in modern calibration laboratories. It discusses how calibration laboratories can meet customer demands while maintaining compliance with standards. Specifically, it reviews practical techniques for managing the risk of incorrect pass/fail decisions in high-volume calibration labs. It explains that statements of compliance carry some risk of being incorrect due to measurement uncertainty. The document discusses how to quantify this risk at both the individual measurement level and overall calibration program level in line with standards like ANSI/NCSL Z540.3. Key aspects covered include test uncertainty ratio, end of period reliability, and how they relate to the probability of false acceptance.
Quality Assurance of Laboratory Test Results based on ISO/IEC 17025PECB
The document discusses quality assurance of laboratory test results based on ISO/IEC 17025. It discusses the importance of analytical measurement data and ensuring results are accurate and precise. It describes internal quality control procedures like spikes, blanks, and replicates that analysts use to ensure results are correct. It also discusses external quality assurance like participating in inter-laboratory comparisons and proficiency testing schemes. The document emphasizes that laboratories must have quality control procedures to monitor validity of tests and ensure trends in results are detectable.
- Reliability is a measure of reproducibility of a test when repeated, quantifying random error. Validity is how well a test measures what it intends to, requiring comparison to a criterion.
- Reliability is typically quantified by the typical error or intraclass correlation. Validity uses correlation and error of estimate from regression of the test on a criterion.
- Both reliability and validity should be high for a test to accurately track small individual changes over time and distinguish individuals. Ideal values are >0.96 for reliability and validity correlations and typical/estimate errors <20% of between-subject standard deviation.
Designing an appropriate qc design procedure for your lab 5 mar15Randox
This document discusses the importance of quality control (QC) procedures in laboratories and provides five simple steps for effective QC. It emphasizes that the goal of QC is to ensure accurate and reliable test results in order to avoid harming patients. The five steps include: 1) identifying quality specifications for each test, 2) choosing good quality control materials, 3) starting and ending patient testing with QC evaluation, 4) understanding good QC results, and 5) recognizing and addressing out-of-control events. Participation in an external quality assessment scheme is also recommended to help detect errors. The document stresses applying QC procedures appropriately based on each test's performance and prioritizing high-risk tests.
Designing an appropriate QC procedure for your laboratoryRandox
Improving Laboratory Performance Through Quality Control - Five Simple Steps for QC Success.
It is easy to get caught up in an abundance of QC statistics and forget the fundamental reason why
QC exists in the first instance. QC is about detecting errors and ensuring that the results you
produce are accurate and reliable. All QC procedures should focus on reducing the risk of harm
to the patient. We are not examining statistics; we are examining real patients, real results and real
lives. Around 70% of all medical decisions are based on laboratory results, which is why it is of
utmost importance that each and every laboratory, has a well-designed QC procedure in place.
The document discusses key concepts for interpreting clinical biochemical data, including:
1. Calculating measures of central tendency like the mean and measures of variability like the standard deviation and range to establish normal reference values.
2. Factors that determine the validity and reliability of analytical tests, and the importance of quality assurance and quality control.
3. Methods for describing data distribution including the coefficient of variation and using critical differences to determine the clinical significance of changes in serial measurements.
4. Concepts related to screening tests like sensitivity, specificity, and the ability to correctly identify individuals with and without the disease.
Effective handling of OOS investigations involves adhering to OOS investigation guidelines to ensure thorough analysis and resolution. Following robust protocols and regulatory standards in OOS investigation processes is crucial for maintaining product quality and compliance.
Read more here https://www.ipa-india.org/wp-content/uploads/2023/05/Presentation-on-Handling-OOS-Investigations-Regulatory-Expectations-Dipesh-Shah-Comsumer-Safety-Officer-USFDA.pdf
FDA OOS investigation India (Out of Specifications).pdfmidohamada2
Dipesh Shah, a consumer safety officer, discusses regulatory expectations for handling out-of-specification (OOS) investigations in India. The guidance outlines a two-phase process for OOS investigations to determine if a result was due to a laboratory error or a production issue. Phase I involves a laboratory investigation and Phase II involves a full production review if no error is found. The guidance stresses that investigations must be scientifically sound, supported by evidence, and result in effective corrective actions to prevent future OOS results. Common problems cited include failing to identify the root cause or evaluate the impact on other batches.
Measurement risk and the impact on your processes Transcat
Howard Zion, Transcat's Director of Service Application Engineering, discusses how measurements are incorrectly influencing the acceptance decision on your products. This webinar will teach you:
What is Measurement Risk?
Where does risk creep into your process?
Where does risk creep into the calibration process?
Calibration Results: Impact on your process
The document discusses the application of statistical tools to enhance productivity and quality control in industries. It explains key concepts like process control, process capability indices, acceptance sampling plans, and their use in quality management. Statistical process control techniques like control charts are used to monitor processes and make data-driven decisions about product and process quality. Acceptance sampling balances protecting consumers from defects and encouraging quality production.
Metrology & The Consequences of Bad Measurement DecisionsRick Hogan
This document discusses the importance of metrology and the consequences of bad measurement decisions. It provides examples of failures that resulted from one or more inadequate elements: requirements that were not linked to performance, uncalibrated equipment, and improper measurement procedures. Consequences ranged from mission failures costing over $1 billion to loss of life. Ensuring measurements have good requirements, equipment, and processes is critical to making correct decisions and avoiding risk.
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Carbonyls undergo addition reactions with a large range of nucleophiles.
Comparing the relative basicity of the nucleophile and the product is extremely helpful in determining how reversible the addition reaction is. Reactions with Grignards and hydrides are irreversible. Reactions with weak bases like halides and carboxylates generally don’t happen.
Electronic effects (inductive effects, electron donation) have a large impact on reactivity.
Large groups adjacent to the carbonyl will slow the rate of reaction.
Neutral nucleophiles can also add to carbonyls, although their additions are generally slower and more reversible. Acid catalysis is sometimes employed to increase the rate of addition.
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptxMAGOTI ERNEST
Although Artemia has been known to man for centuries, its use as a food for the culture of larval organisms apparently began only in the 1930s, when several investigators found that it made an excellent food for newly hatched fish larvae (Litvinenko et al., 2023). As aquaculture developed in the 1960s and ‘70s, the use of Artemia also became more widespread, due both to its convenience and to its nutritional value for larval organisms (Arenas-Pardo et al., 2024). The fact that Artemia dormant cysts can be stored for long periods in cans, and then used as an off-the-shelf food requiring only 24 h of incubation makes them the most convenient, least labor-intensive, live food available for aquaculture (Sorgeloos & Roubach, 2021). The nutritional value of Artemia, especially for marine organisms, is not constant, but varies both geographically and temporally. During the last decade, however, both the causes of Artemia nutritional variability and methods to improve poorquality Artemia have been identified (Loufi et al., 2024).
Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
Or: Beyond linear.
Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
ESR spectroscopy in liquid food and beverages.pptxPRIYANKA PATEL
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
Unlocking the mysteries of reproduction: Exploring fecundity and gonadosomati...AbdullaAlAsif1
The pygmy halfbeak Dermogenys colletei, is known for its viviparous nature, this presents an intriguing case of relatively low fecundity, raising questions about potential compensatory reproductive strategies employed by this species. Our study delves into the examination of fecundity and the Gonadosomatic Index (GSI) in the Pygmy Halfbeak, D. colletei (Meisner, 2001), an intriguing viviparous fish indigenous to Sarawak, Borneo. We hypothesize that the Pygmy halfbeak, D. colletei, may exhibit unique reproductive adaptations to offset its low fecundity, thus enhancing its survival and fitness. To address this, we conducted a comprehensive study utilizing 28 mature female specimens of D. colletei, carefully measuring fecundity and GSI to shed light on the reproductive adaptations of this species. Our findings reveal that D. colletei indeed exhibits low fecundity, with a mean of 16.76 ± 2.01, and a mean GSI of 12.83 ± 1.27, providing crucial insights into the reproductive mechanisms at play in this species. These results underscore the existence of unique reproductive strategies in D. colletei, enabling its adaptation and persistence in Borneo's diverse aquatic ecosystems, and call for further ecological research to elucidate these mechanisms. This study lends to a better understanding of viviparous fish in Borneo and contributes to the broader field of aquatic ecology, enhancing our knowledge of species adaptations to unique ecological challenges.
3. Introduction
• Laboratory analysis is part of conformity assessment
• Conforming with the product specification stated in a sales contract
• Attesting the test result in compliance with a regulatory limit or tolerance level
• General statement of conformity includes:
• Conformance vs Non-conformance
• Compliance vs Non-compliance
• Acceptance vs Rejection
• Pass vs Fail
• Positive vs negative
• Presence vs absence
• A decision based on the tests and measurements must be made before issuing such statement. A set
of decision rules is to be established.
3
4. Introduction
• There is always a risk to make a wrong decision
• Tests done on a laboratory sample; how representative is the
sample?
• Test results are always associated with measurement
uncertainty
• Decision may be “biased” due to someone’s possible vested
interest
• Are we able to control such risk in order to make an
informed decision?
4
5. Definitions of “Decision Rule”
• ISO/IEC 17025:2017 clause 3.7: “Rule that describes how
measurement uncertainty is accounted for when stating conformity
with a specified requirement”
• ISO Guide 98-4, JCGM 106: “Documented rule that describes how
measurement uncertainty will be accounted for with regard to
accepting or rejecting an item, given a specified requirement and the
result of a measurement”
• Eurachem Guide on Compliance Assessment: “A documented rule
that describes how measurement uncertainty will be allocated with
regard to accepting or rejecting a product according to its
specification and the result of a measurement”
5
6. Therefore, decision rule is a rule taking measurement
uncertainty into account when stating conformity
with a specification value or compliance with a
regulatory limit.
When making a claim of non-conformity, the risk should be as
low as possible for false rejection, i.e., we should have high
confidence to correctly reject the test result.
6
8. Relevant clauses of ISO/IEC 17025:2017
• Clause 6.2.6 requires that the laboratory shall authorize
personnel to “analyse results, including statements of
conformity or opinions and interpretations”. That implies only
authorized signatories are allowed to handle decision making
in this case.
• The laboratory is now required to record the decision rule
adopted taking into account the risk; such a rule will have on
reporting false positive or negative results. (Ref: clause 7.1.3)
8
9. Relevant clauses 7.1.3 of ISO/IEC 17025:2017
• 7.1 Review of requests, tenders and contracts
• 7.1.3 When a customer requests a statement of conformity
to a specification or standard for the test or calibration (e.g.
pass/fail, in-tolerance/out-of-tolerance) the specification or
standard, and the decision rule shall be clearly defined. Unless
inherent in the requested specification or standard, the
decision rule selected shall be communicated to, and agreed
with, the customer.
9
10. Relevant clauses 7.8.6 of ISO/IEC 17025:2017
• 7.8.6 : Reporting statements of conformity
• 7.8.6.1 When a statement of conformity to a specification
or standard is provided, the laboratory shall document the
decision rule employed, taking into account the level of
risk (such as false accept and false reject and statistical
assumptions) associated with the decision rule employed,
and apply the decision rule.
• NOTE: Where the decision rule is prescribed by the
customer, regulations or normative documents, a further
consideration of the level of risk is not necessary.
10
11. Relevant clauses 7.8.6 of ISO/IEC 17025:2017
• 7.8.6 Reporting statements of conformity (contd.)
• 7.8.6.2 The laboratory shall report on the statement of conformity, such
that the statement clearly identifies:
• a) to which results the statement of conformity applies;
• b) which specifications, standards or parts thereof are met or not met;
• c) the decision rule applied (unless it is inherent in the requested
specification or standard).
The laboratory shall report on the statement of conformity, such that the
statement clearly identifies:
• To which results the statement of conformity applies;
• Which specifications, standards or parts thereof are met or not;
• The decision rule applied
11
12. To make a decision rule, we must have….
• A measurand (analyte) clearly specified (i.e. specification of the
object)
• A test result (normally assuming normal distribution of test results)
• Its associated measurement uncertainty
• A specification or regulation giving upper and/or lower limits
• A decision rule
This rule can decide to take or not to take measurement uncertainty
into account, but it includes the risk of making a wrong decision,
of which the involved parties are willing to take.
12
13. Aims of making a decision rule
• One should be clear on what type of risk he is taking
when making a proper decision rule:
• the supplier’s (laboratory’s) risk (Type I error, ) or
• the consumer’s (customer’s) risk (Type II error, )
• From the laboratory point of view, we should be looking
at Type I () False Positive error, as we want to minimize
and control our risk in issuing a statement of conformity
that might be proven wrong later.
• We usually set the error or risk that we can afford to take,
e.g. = 0.05 (or 5%), bearing in mind that our test results
have associated measurement uncertainties.
13
Important assumption: The
uncertainty of measurement
is represented by a normal
(Gaussian) probability
distribution function, which is
consistent with the typical
measurement results (being
assumed the applicability of
the Central Limit Theorem)
14. What is Type I () error?
• A type I error is caused by wrongly rejecting a true (“Pass”) situation
(statistically speaking, a null hypothesis Ho)
• This happens when the test result is found to be close to the specification
value.
• In a hypothesis (significance) testing, we write:
• Null hypothesis Ho : test result = specification value (not literally but with probability)
• Alternate hypothesis H1 : test result > or < specification value (depending on the
upper or lower limits of specification)
• Generally, we want to control our error (risk) when making a statement to
reject Ho, i.e., saying the test result fails to meet with the given specification
limit
• We normally fix such error at = 0.05, or 5% error (or 95% confidence)
14
15. Today’s practice on decision rules
• In current practice, we have been making a very simple decision
rule, often based on direct comparison of measurement value
with the specification or regulatory limits.
• The reason is either that
• these limits are deemed to have assumed including the measurement
uncertainty, which is not normally true,
• or, it has been assumed that the measurement value has zero
uncertainty!
• But, due to the presence of uncertainty in all measurements,
we are actually taking more than 50% risk to allow the actual
true value of the test parameter found outside the
specification when reporting the measurement value exactly
on the specification limit. 15
>50% Risk
above
specification
limit!
Specification-
upper limit
(Maximum)
16. A worked example
• Suppose a test method has a measurement uncertainty (+ 0.35ppm)
of a lead Pb content near its upper feed product specification limit
of 10ppm.
• Upon analysis, a result of 9.65+0.35ppm was found in the feed
sample given with 95% confidence.
• This result indicates that the true Pb content of the sample is
somewhere within the range: 9.30ppm to 10.00ppm with 95%
confidence
• It means that there is 2.5% chance that the true Pb content is
outside both ends of this range. 16
17. The meaning of Measurement Uncertainty
◼ For a measured value of 9.65ppm with an uncertainty of
0.35ppm, we shall write :
◼ 9.65 + 0.35 ppm
◼ The uncertainty range covers :
◼ 9.30 – 10.00 ppm with 95% confidence that the true value will
lie somewhere within:
◼ 9.30 9.65 10.00 ppm
◼ (True Value)
17
=0.025 uncertainty
=0.025 uncertainty
18. A worked example
• Remember that this uncertainty
(U) of +0.35 ppm comes from
• 2 x 0.175 ppm
• where 2 is the coverage factor
for normal distribution at about
95% confidence and,
• 0.175 ppm is the combined
standard uncertainty (u) from
the MU evaluation study.
• To be exact, the coverage factor
should be 1.96 for 95.00%
confidence for two-tailed
distribution situation (+).
By MS Excel functions:
-1.9600 =NORM.INV(0.025,0,1)
1.9600 =NORM.INV(0.975,0,1)
18
19. Use of Excel functions for normal distribution
Excel® entry
-1.960 =NORM.INV(0.025,0,1)
1.960 =NORM.INV(0.975,0,1)
0.975 =NORM.DIST(1.96,0,1,TRUE)
0.950 =NORM.DIST(1.645,0,1,TRUE)
“=NORM.INV(probability, mean, standard_deviation)”
“=NORM.DIST(x, mean, standard_deviation, cumulative)”
Proportion of area under the curve from - to
z- value. When mean = 0 and SD = 1, x = z.
19
z =
z =
20. A worked example
• Hence, if we were to decide on 9.65 ppm as our critical value to
make a “Pass” statement of conformity with confidence, we are
actually taking a 2.5% risk, instead of 5.0%, to be proven wrong if
the same sample were to be tested elsewhere by the same
procedure.
• But we are prepared to take a usual 5% risk in making such
statement.
• What is the critical value if we wish to make a decision rule to
take a 5% risk (or making a 5% error in rejecting the test result)
instead?
20
21. A worked example
• Remember the product
specification’s upper limit is 10.0
ppm Pb
• Our concern therefore is how
much uncertainty of our test
result is in the rejection zone
above the 10 ppm limit
• Hence, the coverage factor should
be chosen at the right-tailed
normal distribution instead of
two-tailed distribution.
• This coverage factor = 1.645,
instead of 1.960 under normal
probability distribution.
By MS Excel function:
-1.6449 =NORM.INV(0.05,0,1)
1.6449 =NORM.INV(0.95,0,1)
21
22. A worked example
• Therefore, the critical value for us to take a 5% risk to reject the result
against the upper specification limit is therefore:
• 10.00 – 1.645 x 0.175 or 10.00 – 0.288 or 9.71 ppm Pb
• That means our decision rule can be stated as below:
• “A pass statement shall be reported when the test result is equal or
smaller than 9.71 ppm Pb content in the feeds with 95% confidence. A
provisional or conditional pass can be reported when the test result is
above 9.71 ppm Pb but below 10.00 ppm Pb. A fail statement is to be
declared for test results above 10.00 ppm Pb. ”
22
23. In summary, graphical effect of the decision rules:
Specification:
10.0 ppm Max
9.65 ppm
9.71 ppm
U = 0.35 ppm U = 0.29 ppm
2.5% Risk 5.0% Risk
Acceptance Zone
Rejection Zone
23
24. Use of Guard Band g with acceptance limits
• ILAC-G8, Eurolab documents suggest the use of Guard
Band g which is the current trend of thinking.
• Guard band (g) is defined as: “interval between a
tolerance limit and a corresponding acceptance limit
where length g = |TL – AL|.”
Upper Tolerance Limit TL
Lower Tolerance Limit TL
Acceptance Limit AL
Acceptance Limit AL
g
g
Nominal
24
25. A graphical example of areas defined for a specification
interval with guard bands
+ U
25
26. Example 1A of areas defined for a specification interval with
guard bands inside the set limits – conservative or stringent
acceptance zone (Type I ) model
26
In this model, the risk taken is 2.5% at = 0.025 only at upper or lower specification limits
27. Example 1B of areas defined for a specification interval with
guard bands inside the set limits – conservative or stringent
acceptance zone (Type I ) model
In this model, the risk taken is 5% at = 0.05 only at upper or lower specification limits
27
28. Example 2 of areas defined for a specification interval with
guard bands outside the set limits – Relax rejection zone
(Type II ) model
28
29. Example 3 of areas created by considering the upper and lower
tolerance limits given by the customer with the laboratory’s
own measurement uncertainty
29
30. Similar approaches for microbiological counts
• Microbiological analysis is based on counting the number of colonies in
terms of CFU (Colony Forming Units) after incubation with appropriate
agar media.
• Discrete counting does not follow normal probability distribution.
• A logarithmic transformation of the counts is to be made in order to
assume a normal distribution for continuous data
• For example, for a count of 100 CFU, Log10(100) = 2.000
• In MU study of microbiological counts, the combined standard
uncertainty is expressed in the form of logarithmic relative standard
deviation, Log10, rel
• Same principles of factor 1.645 are applied like those in chemical analysis.
30
31. The binary
approach
• Applicable for qualitative “Pass/Fail”, “Present/Absent”,
etc. testing
• When you take two samples for testing and if both pass,
you report “Pass”
• If one passes and another fails, then you need to take
two more samples for analysis
• If both pass, it is determined as a pass
• If either or both fail, it fails.
• This approach has implicitly taken uncertainty into
account and is therefore the defined “decision rule”
31
32. In reporting ….
• The laboratory shall :
• apply the decision rule
• Ensure its report to contain either the decision rule used or a reference to a standard
or agreed decision rule
• Listing the uncertainty of measurement result is optional, depending on customer’s
liking
• Making a disclaimer statement, e.g. by ILAC Guide 8.03 “The statement(s) of
compliance with specification (or requirement) is based on a 95% coverage probability
for the expanded uncertainty of the measurement results on which the decision of
compliance is based”.
• There must be enough detail so that if another lab is tasked with taking the same
measurements and using the same decision rule, that they will come to the same
conclusion about a “pass” or “fail”, in order to avoid any legal implication.
32
33. Decision rule documentation, the lab shall ….
33
document the decision rules
employed taking into account the
level of risk associated with the
decision rule employed (i.e. false
accept and false reject) and statistical
assumptions associated with the
decision rule employed;
prepare a list of critical values for the
test parameters with Type I error α =
0.05, i.e. 95% confidence, normally
after some statistical hypothesis
analysis
take time to clearly document what
has been agreed with the clients and
ensure that lab procedures allow for
the correct treatment of the readings
and uncertainties
might need to change test procedures
to cater for the decision rule that will
be applied such as a review of
measurement uncertainty level. It has
to be such that anybody in the lab
will know what is required and what
the limits are.
34. Parting words ….
• Decision rule construction requires four components:
• the measurement result,
• its measurement uncertainty,
• the specification limit or limits, and
• the acceptable level of the probability of making
each type of wrong decision.
• Choice of a decision rule is a business consideration
that takes into account the cost of rejecting an in-
specification product, the cost of accepting an out-of-
specification product, the uncertainty associated with
the measurement, the cost of making the measurement,
and client’s relationship for future business.
34
35. i.e., the lab must agree with the customer on its decision rule and
communicate clearly about the level of risk associated with this
decision rule.
Conclusions
• Issuance of a certificate of conformity or a statement of
compliance allows the laboratory to carry a fair bit of
responsibility.
• The laboratory must be confident on its own measurement
uncertainty estimation.
• If a statement of conformity is required by the clients, a lot
more detail is required to be discussed before carrying out
the laboratory analysis.
• ISO/IEC 17025 requires the Lab to be very clear about the
criteria used and must communicate with and be agreed by
the customer, defined in the test report, certificate of
conformance or statement of compliance to avoid future
disputes.
35
36. Useful References
• ILAC-G8:09/2019 : Guidelines on Decision Rules and Statements
of Conformity
• EuroLab Technical Report No. 01/2017 : Decision rules applied to
conformity assessment
• UKAS LAB 48 Edition 3 (June 2020) : Decision rules and
statements of conformity
• OIML Guide G 19 (2017) : The role of measurement uncertainty in
conformity assessment decisions in legal metrology
• JCGM 106:2012 : Evaluation of measurement data – The role of
measurement uncertainty in conformity assessment
36