Basic concepts of Quality

Since the 'quality' had legal aspects the consistent, professional formulation has been essential. Thus, the European Organization for Quality created the International Quality Definitions Dictionary from which I quote some definitions :
Quality Requirement : A set of metrics which is used to be quantified the requests in regulation form in order to describe and evaluate quality of the product or service.
Specification : Accurate specification outlining system capabilities algorithms (incl. capabilities and limitations)
Conformity : manufacturer's details, essential characteristics the product complies; any European standards and performance data; if relevant the identification number of the Notified Body; and a legally binding signature on behalf of the organization.
Quality Assurance, QA : All planned and systematic actions necessary to provide confidence that a product will satisfy requirements for quality.
Quality Control, QC : The regulatory process through which the actual quality performance is measured, compared with existing standards, and the actions necessary to keep or regain conformance with the standards.
There are two types of quality systems in Europe:

1. Standardization system: the manufacturer / supplier only should declare the compliance of the standard, testing or certification institute such as third-party involvement is not mandatory.
2. Official system: Where accredited testing and certification bodies contribution is required. Generally, this includes the health care as well.

Accreditation : it is the establishment of the status, legitimacy or appropriateness of an institution, programme (i.e. composite of modules) or module of study.
Calibration : is a comparison between measurements – one of known magnitude or correctness made or set with one device and another measurement made in as similar a way as possible with a second device.

International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources in the Appendix II. give a definition of quality assurance programmes for medical exposure.
Quality assurance programmes for medical exposures shall include:
(a) measurements of the physical parameters of the radiation generators, imaging devices and irradiation installations at the time of commissioning and periodically thereafter;
(b) verification of the appropriate physical and clinical factors used in patient diagnosis or treatment;
(c) written records of relevant procedures and results;
(d) verification of the appropriate calibration and conditions of operation of dosimetry and monitoring equipment; and
(e) as far as possible, regular and independent quality audit reviews of the quality assurance programme for radiotherapy procedures.

Monitoring of measuring, testing and checking indicators condition

The point of the activity:

• All of the instruments, which indicated / measured results whether are critical regarding the effectiveness of the treatment, or these are important in respect to radiation exposure of workers, they always have to be in perfect technical condition and must have the necessary authentication.
• Must be kept a log book from all the indicators which have to be periodically calibrated and certified. It contains the identification and list of the indicators . The quality manual contains periodic validations / calibrations schedule.

 
Head of Medical Physics Department is responsible for the calibration procedures should be adequately documented and they are also regularly carried out. In this connection, his/her round of duties are in below:

• Determine the measurements to be carried out and decide about equipment and accuracy of measurements.
• All instruments that may be affected on the treatments, has to be fit with proper identification and set before use or at specified intervals has to be checked with calibrated instrument which ensures the traceability of the test results to the national benchmark. If there is no such possibility, the whole "calibration" process should be documented .
• Need to develop procedures for calibration and they should be documented and maintained. Hence, in addition to the data (type, serial number, identification, invention location, frequency of testing, test method) relative to equipments the compliance requirements should also be recorded, and must describe what to do if the instrument which is tested does not meet the specifications.
• Must be ensured that the measuring and control instruments have the required accuracy and reproducibility.
• The instruments need to be fitted with proper signs to be visible that these are calibrated and the calibration is valid.
• The instrument calibration records should be filed.
• If an instrument validation has expired, the instrument further usability can be decided in virtue of the evaluation of pre-authentication reports, and the result of this shall be recorded in the report.
• Must be looked after that the calibrations and measurements should happen in suitable environmental conditions.
• The proper storage of equipments must be ensured.
• Must be ensured that an unauthorized person does not carry out any changes (including changes in the software as well) on the instruments which influence their authentication /calibration, and herewith invalidate this.

 

References

 
1. Biggs, D. S., Thomson, E. S., Ball, K. A>: Implementation of ISO 9000 in a radiotherapy physics department. Rad. Közl. 33, Suppl. 1. 25-29 (1997)
2. ISO 9002 Quality systems. Model for quality assurance in production, installation and servicing. 1987. (angol változat: BS 5750, adaptálása a sugárterápiára a QART 3.
3. Bleehen 1991 Quality Assurance in Radiotherapy. Report of a Working Party of the Standing Subcommittee on Cancer of the Standing Medical Advisory Committee May 1991 (London: Department of Health)
4. BS EN ISO 9002: 1994 Quality systems. Model for quality assurance in production, installation and servicing.
5. EC 1997 Council Directive 97/43/EURATOM 30 June 1997. Health Protection of Individuals Against the Dangers of Ionizing Radiation in Relation to Medical Exposure Official Journal of the European Communities OJ No L180/22
6. 31/2001. (X. 3.) EüM rendelet Az egészségügyi szolgáltatások nyújtása során ionizáló sugárzásnak kitett személyek egészségének védelmérõl
7. IPEM 81 Physics Aspects of Quality Control in Radiotherapy (Edts.: W.P.M. Mayles, R. Lake, A. McKenzie, E.M. Macaulay, H.M. Morgan, T.J. Jordan and S.K. Powley) The Institute of Physics and Engineering in Medicine. York, 1999 ISBN 0 904181 91 X

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