1.1 What is Quality?
1.2 Quality Management
1.3 Quality Assurance
1.4 Quality Control
1.5 Good Laboratory Practice (GLP)
Since this manual is aimed at improving the performance of a laboratory, the activities involved focus on the term "quality". The quality of the product, in the present case analytical results, should obviously be acceptable. To establish whether the product fulfils the quality requirements these have to be defined first. Only after that it can be decided if the product is satisfactory or if and what corrective actions need to be taken.
The term "quality" has a relative meaning. This is expressed by the ISO definition: "The totality of features and characteristics of a product or service that bear on its ability to satisfy stated or implied needs". In simpler words, one can say that a product has good quality when it "complies with the requirements specified by the client". When projected on analytical work, quality can be defined as "delivery of reliable information within an agreed span of time under agreed conditions, at agreed costs, and with necessary aftercare". The "agreed conditions" should include a specification as to the precision and accuracy of the data which is directly related to "fitness of use" and which may differ for different applications. Yet, in many cases the reliability of data is not questioned and the request for specifications omitted. Many laboratories work according to established methods and procedures which are not readily changed and have inherent default specifications. Moreover, not all future uses of the data and reports can be foreseen so that specifications about required precision and accuracy cannot even be given. Consequently, this aspect of quality is usually left to the discretion of the laboratory. However, all too often the embarrassing situation exists that a laboratory cannot evaluate and account for its quality simply because the necessary documentation is lacking.
In the ensuing discussions numerous activities aimed at maintaining the production of quality are dealt with. In principle, three levels of organization of these activities can be distinguished. From the top down these levels are:
1. Quality Management (QM)
2. Quality Assurance (QA)
3. Quality Control (QC)
Quality Management is the assembly and management of all activities aimed at the production of quality by organizations of various kinds. In the present case this implies the introduction and proper running of a "Quality System" in laboratories. A statement of objectives and policy to produce quality should be made for the organization or department concerned (by the institute's directorate). This statement also identifies the internal organization and responsibilities for the effective operation of the Quality System.
Quality Management can be considered a somewhat wider interpretation of the concept of "Good Laboratory Practice" (GLP). Therefore, inevitably the basics of the present Guidelines largely coincide with those of GLP. These are discussed below in Section 1.5.
Note. An even wider concept of quality management is presently coming into vogue: "Total Quality Management" (TQM). This concept includes additional aspects such as leadership style, ethics of the work, social aspects, relation to society, etc. For an introduction to TQM the reader is referred to Parkany (1995).
Proper Quality Management implies consequent implementation of the next level: Quality Assurance. The ISO definition reads: "the assembly of all planned and systematic actions necessary to provide adequate confidence that a product, process, or service will satisfy given quality requirements." The result of these actions aimed at the production of quality, should ideally be checked by someone independent of the work: the Quality Assurance Officer. If no QA officer is available, then usually the Head of Laboratory performs this job as part of his quality management task. In case of special projects, customers may require special quality assurance measures or a Quality Plan.
A major part of the quality assurance is the Quality Control defined by ISO as "the operational techniques and activities that are used to satisfy quality requirements. " An important part of the quality control is the Quality Assessment: the system of activities to verify if the quality control activities are effective, in other words: an evaluation of the products themselves.
Quality control is primarily aimed at the prevention of errors. Yet, despite all efforts, it remains inevitable that errors are be made. Therefore, the control system should have checks to detect them. When errors or mistakes are suspected or discovered it is essential that the "Five Ws" are trailed:
- what error was made?
- where was it made?
- when was it made?
- who made it?
- why was it made?
Only when all these questions are answered, proper action can be taken to correct the error and prevent the same mistake being repeated.
The techniques and activities involved in Quality Control can be divided into four levels of operation:
1. First-line control: Instrument performance check.
2. Second-line control: Check of calibration or standardization.
3. Third-line control: Batch control (control sample, identity check).
4. Fourth-line control: Overall check (external checks: reference samples, interlaboratory exchange programmes).
Because the first two control levels both apply to the correct functioning of the instruments they are often taken together and then only three levels are distinguished. This designation is used throughout the present Guidelines:
1. First-line control: Instrument check / calibration.
2. Second-line control: Batch control
3. Third-line control: External check
It will be clear that producing quality in the laboratory is a major enterprise requiring a continuous human effort and input of money. The rule-of-fist is that 10-20% of the total costs of analysis should be spent on quality control. Therefore, for quality work at least four conditions should be fulfilled:
- means are available (adequate personnel and facilities)
- efficient use of time and means (costs aspect)
- expertise is available (answering questions; aftercare)
- upholding and improving level of output (continuity)
In quality work, management aspects and technical aspects are inherently cobbled together and for a clear insight and proper functioning of the laboratory these aspects have to be broken down into their components. This is done in the ensuing chapters of this manual.
Quality Management in the present context can be considered a modem version of the hitherto much used concept "Good Laboratory Practice" (GLP) with a somewhat wider interpretation. The OECD Document defines GLP as follows: "Good Laboratory Practice (GLP) is concerned with the organizational process and the conditions under which laboratory studies are planned, performed, monitored, recorded, and reported."
Thus, GLP prescribes a laboratory to work according to a system of procedures and protocols. This implies the organization of the activities and the conditions under which these take place are controlled, reported and filed. GLP is a policy for all aspects of the laboratory which influence the quality of the analytical work. When properly applied, GLP should then:
- allow better laboratory management (including quality management)
- improve efficiency (thus reducing costs)
- minimize errors
- allow quality control (including tracking of errors and their cause)
- stimulate and motivate all personnel
- improve safety
- improve communication possibilities, both internally and externally.
The result of GLP is that the performance of a laboratory is improved and its working effectively controlled. An important aspect is also that the standards of quality are documented and can be demonstrated to authorities and clients. This results in an improved reputation for the laboratory (and for the institute as a whole). In short, the message is:
- say what you do
- do what you say
- do it better
- be able to show what you have done
The basic rule is that all relevant plans, activities, conditions and situations are recorded and that these records are safely filed and can be produced or retrieved when necessary. These aspects differ strongly in character and need to be attended to individually.
As an assembly, the involved documents constitute a so-called Quality Manual. This comprises then all relevant information on:
- Organization and Personnel
- Equipment and Working materials
- Analytical or testing systems
- Quality control
- Reporting and filing of results.
Since institutions having a laboratory are of divergent natures, there is no standard format and each has to make its own Quality Manual. The present Guidelines contain examples of forms, protocols, procedures and artificial situations. They need at least to be adapted and many new ones will have to be made according to the specific needs, but all have to fulfil the basic requirement of usefulness and verifiability.
As already indicated, the guidelines for Quality Management given here are mainly based on the principles of Good Laboratory Practice as they are laid down in various relevant documents such as ISO and ISO/IEC guides, ISO 9000 series, OECD and CEN (EN 45000 series) documents, national standards (e.g. NEN standards)*, as well as a number of text books. The consulted documents are listed in the Literature. Use is also made of documents developed by institutes which have obtained accreditation or are working towards this. This concerns mainly so-called Standard Operating Procedures (SOPs) and Protocols. Sometimes these documents are hard to acquire as they are classified information for reasons of competitiveness. The institutes and persons which cooperated in the development of these Guidelines are listed in the Acknowledgements.
* ISO: International Standardization Organization; IEC: International Electrical Commission; OECD: Organization for Economic Cooperation and Development; CEN: European Committee for Standardization, EN: European Standard; NEN: Dutch Standard.