Laboratories and their clients need to ensure that valid methods of measurement are selected and that there is clear evidence that the methods are capable of measuring what needs to be measured.
This guide provides advice on the concepts and good practice in method validation for quantitative chemical analysis and includes discussion of laboratory accreditation requirements.
It has been produced in response to requests from small laboratories for user-friendly advice on what actually needs to be done when, for example, a previously validated method is used in a laboratory for the first time, or where it is necessary to validate a new method.
The sections of the guide are colour coded for ease of use. For quick reference essential material is arranged in clear highlighted boxes.
The guide was written by Bernard King, with support from colleagues in a number of laboratories: in particular Elizabeth Prichard and Vicki Barwick from LGC. As a past Director at the Laboratory of the Government Chemist of the UK and the National Analytical Reference Laboratory of Australia, Bernard has gained extensive experience of both the selection and validation of chemical methods. He is also a major contributor to international affairs on issues concerned with analytical quality.
The development of the guide was supported under contract with the Department of Trade and Industry as part of the National Measurement System Valid Analytical Measurement (VAM) Programme.
The guide adopts a holistic approach to the inter-related topics of method validation, measurement uncertainty and traceability and takes into account cost-benefit issues when considering the degree of rigour required.
The guide provides a 'route planner' for method validation and is divided into five sections:
Introductory Issues
- How to use the guide
- Some frequently asked questions
- Good measurement practice and accreditation requirements
Selecting a Method and Planning Method Validation
- Specifying measurement requirements
- Describing the measurand
- Selecting a method and measuring equipment
- Deciding the approach and planning validation
- Deciding the degree of rigour - How much is enough?
Key Performance Parameters
- Sampling and sample preparation
- Precision
- Specificity / selectivity
- Bias and its correction
- Measurement equation
- Ruggedness testing
- Calibration and traceability
- Sensitivity, linearity, working range, limit of detection and limit of quantitation
- Evaluating measurement uncertainty
Evaluating and Documenting the Method and its Validation
- Setting method performance parameters and quality control limits
- Documentation
- Final checklist, confirmation that a method is fit for its intended use and change control
Annexes
- References, glossary of terms and equations and abbreviations
- Method validation planning and reporting templates
- Template for recording calculation of performance parameters
- Layout for method documentation
This guide costs �35.
To purchase this, download and complete the order form (PDF), and send it to the VAM helpdesk with your payment.
On-line ordering is no longer available from the VAM website.