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Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement (v.4, #9-10)
The Antwerpen Conference on Quality (R)evolution in Clinical Laboratories is back ...
by Paul De Bièvre (pp. 388-388).
4th European Conference on Quality Management in Clinical Laboratories: Quality [R]evolution in Clinical Laboratories, Antwerp, Belgium,
by J. C. Libeer; H. M. J. Goldschmidt (pp. 389-390).
Analytical quality management: From rules and tools to technology and training by James O. Westgard (pp. 391-396).
Building on last years conference discussion of "mapping the road to analytical quality with OPSpecs charts", this paper focuses on new technology and training to support and improve analytical quality management. Rigorous QC planning is complicated by the need to consider multiple decision levels, differences in method performance at each of these decision levels, multiple formats of quality requirements (allowable total error, medically important changes, biologic goals), and multiple QC designs (e.g., startup design, monitor design, average of normal design). Developments in computer technology can facilate dealing with these complications. In addition, the development of Internet training materials and courses can support and improve the technical management skills of laboratory personnel.
Keywords: Key words Practical QC planning; TQM rules; Operational characteristics; Internet teaching and coaching
The European way to go: Virtual Central Laboratory by Rob T. P. Jansen (pp. 397-400).
In clinical pharmaceutical trials often one central laboratory is used for the analysis of routine parameters, the so-called safety parameters. In many countries the heads of laboratory departments question the quality of such analysis in terms of quality of samples after transport, continuity of patient related medical laboratory information before, during and after the trial; turn around time; alerting procedures and consultancy to requesting physicians. On the other hand, the pharmaceutical industry prefers to work with central laboratories since they can claim certification or accreditation. Also the use of one set of reference values is an important issue, as well as electronic data transfer to the trial organizer's database. The concept of a Virtual Central Laboratory (VCL), initiated in the Netherlands, tries to solve this conflicting situation. In the concept, local hospital laboratories receive computer-assisted aid in the identification of patients, trials, visits and requests. The laboratory data are transformed using calibrator sets to produce a homogeneous data set across laboratories, resulting in one set of reference values. The data are electronically transferred to a central computer from which they are send in any desired format to the trial organizer's database. Participating laboratories are obliged to work towards accreditation. The VCL acts as a central counterpart for both the pharmaceutical industry and local laboratories. The concept offers advantages to the pharmaceutical industry, the investigator and local laboratories.
Keywords: Key words Clinical trials; Laboratory investigation; Virtual networks
From total allowable error via metrological traceability to uncertainty of measurement of the unbiased result by René Dybkaer (pp. 401-405).
The concept of "total allowable error", investigated by Westgard and co-workers over a quarter of a century for use in laboratory medicine, comprises bias as well as random elements. Yet, to minimize diagnostic misclassifications, it is necessary to have spatio-temporal comparability of results. This requires trueness obtained through metrological traceability based on a calibration hierarchy. Hereby, the result is associated with a final uncertainty of measurement purged of known biases of procedure and laboratory. The sources of bias are discussed and the importance of commutability of calibrators and analytical specificity of the measurement procedure is stressed. The practicability of traceability to various levels and the advantages of the GUM approach for estimating uncertainty are shown.
Keywords: Key words Metrological traceability; Total allowable error; Trueness; Unbiased result; Uncertainty of measurement
Analytical quality specification for measurements reported on an ordinal scale by Per Hyltoft Petersen (pp. 406-409).
A model for evaluation of analytical quality specifications for measurements performed on an ordinal scale is described. It is based on the assumption that the quantity, in principle, can be measured on a ratio (or difference) scale by other methods, but is performed by a cheap, simple and rapid method as 0 or 1 (minus or plus). It is not possible to estimate mean and standard deviations from an ordinal scale, so the measurements of 0 or 1 are characterized by the fraction of measured values of 1 for a certain concentration. For a series of increasing (known) concentrations of the quantity, the fractions of measured values of 1 are plotted on a probit scale. For a pregnancy test with measurements on an ordinal scale – measuring urine-human chorionic gonadotropin as minus or plus – allowable fractions of measured values of 1 are defined for the 'true' concentrations of 3 and 25 U/l based on clinical goals for early detection of pregnancy.
Keywords: Key words Analytical quality goals; Measurement scales; Probit transformation
Quality specifications in laboratory medicine – current consensus views by Callum G. Fraser (pp. 410-413).
Every analytical method used in laboratory medicine can be fully described in terms of its performance characteristics. Ideally, quality specifications should be available for all of these, particularly precision and bias. Specifications for these can be set using a variety of strategies. Consideration of the clinical settings of monitoring individual patients and diagnosis using reference intervals shows that generally applicable quality specifications can be based on the components of biological variation, namely, within-subject [CVI] and between-subject [CVG] variation. Current consensus is that precision should be <1/2CVI and bias should be <1/4[CVI 2+CVG 2]1/2. This strategy has advantages in that data on components of biological variation are easily available on more than 180 quantities. Dissemination of information on application of objective quality specifications needs attention from those involved in publication, manufacturers and organisers of external quality assessment schemes.
Keywords: Key words Analytical goals; Quality specifications; Precision; Bias; Biological variation
External quality assurance of test requesting and test interpretation by S. Sandberg; Geir Thue (pp. 414-415).
The ultimate product of the clinical laboratory is not a number, but an advice. To what quality standards should this advice live up to? In external quality assurance for primary health care in Norway, case histories are mailed together with the analytical quality control material. The analytical result of the control material is used in the case history. The feedback reports discuss clinical guidelines as well as the influence of analytical variation on clinical decision-making.
Keywords: Key words Primary health care; Consultation; Feedback reports; Medical decision-making; Clinical guidelines
Charts of operational process specifications (OPSpecs charts): Quality-planning tools for analytical and medical needs
by Diler Aslan (pp. 416-418).
Point-of-care testing: Implementation and practice of cost-effective total quality management by S. S. Ehrmeyer; Ronald H. Laessig (pp. 419-422).
In the United States of America, point-of-care testing (POCT) generally is defined as laboratory testing performed at or near the patient. The objective is to have results immediately available to clinicians for timely medical intervention. The widespread use of POCT is, in part, a response to advances in technology and increased patient acuity. Theoretically, in the context of the entire health care system, POCT improves "quality" by promoting cost through quicker diagnosis and treatment, which in turn leads to faster recovery, reduced length of stay, more efficient clinicians, and overall better utilization of resources. Total quality management (TQM) generally is associated with improving processes and, therefore in this context, improving patient outcomes. The TQM philosophy focuses on creating products or services, which meet or exceed customer expectations. The successful implementation of POCT in a manner consistent with TQM principles requires assessment of direct, measurable benefits including cost-effectiveness to the health care system.
Keywords: Key words Point-of-care testing; Total quality management; Quality mandates; Outcome measurements
Implementation of a quality system in a clinical laboratory by Maritta Siloaho (pp. 423-426).
The effects of a quality system are measured with the aid of quality indicators, which can be used for both decision-making by the management of the laboratory and for process control. The need for economic appraisal is stressed since the development of a quality system is very time- and labour-consuming. The aspects of both the customer and the personnel involved should be considered to evaluate the quality system. It is also important to define practical means to build up and maintain a quality system especially in smaller laboratories. For instance, simple tools to evaluate uncertainty of measurement and availability of inexpensive national reference materials are needed.
Keywords: Key words Practical quality management; Quality indicators; Human involvement; Quality
Delivering quality for the measurement of immunosuppressive drugs: current performance and future needs by David W. Holt; A. Johnston (pp. 427-430).
Whilst it is generally agreed that measurement of immunosuppressive drugs is of value as a guide to therapy, there are a number of problems associated with the analytical techniques available. Proficiency testing schemes enable laboratories to judge their performance for the measurement of these drugs with their peers. However, current schemes only compare accuracy within-methods to document performance. This paper summarizes current findings and points out the limitations of our own schemes, and the measures we intend to use to address these deficiencies.
Keywords: Key words Drugs proficiency testing; Analytical quality indicators; Calibrator material; Traceability
Use of averages of patient data for quality control by D. Aslan; F. Kuralay; T. Tanyalsin; M. Topraksu (pp. 431-433).
Applicability of Hoffman's average of normals (AON) method was evaluated in quality control (QC) for twenty clinical chemistry assays (ALT, Alb, ALP, AMY, AST, T. Bil, inP, Glu, Ca, Cl, T. Chol, Creat, CK, K, LD, T. Prot., Na, TG, BUN, Uric. A.) performed routinely in the Hospital of Medical Faculty of 9 Eylül University. Consecutive Texas Instruments XL-Dacos patient data were accumulated over 10 days. According to the guidelines developed by Cembrowsky et. al. for the implementation of average of patients (AOP) (also known as AON) procedure, the patient population mean, *p, population standard deviation, Sp, the ratio of Sp/Sa (Sa, the analytical standard deviation), and the approximate number of patient results averaged. Np (with Ped=0.50) were determined from the nomogram constructed by Cembrowsky et. al., illustrating the relationship between Np, Sp/Sa, and the probability of detecting a 2Sa shift (Ped) when the probability of false rejection, Pfr, is 0.01. The control limits and the truncation limits were selected as *p±2Sp and *p±2.58×Sp√Np, respectively. The estimated values were assessed for the applicability of AOP procedures in the clinical laboratory. We conclude that the AOP procedure is a valuable tool for instrument monitoring as an adjunct to more costly standard QC procedures and is also an efficient, cost-effective and rapid way of collecting appropriate information on large number of patients.
Keywords: Key words Daily quality control; Patients' data statistics; Control limits; Truncation limits
The Virtual Central Laboratory approach for the retrieval and management of clinical laboratory data for clinical studies by R. Scholten; Jaap H. M. Dijkman (pp. 434-435).
In 1996, the Virtual Central Laboratory (VCL) concept was presented at the 2nd Conference on Quality [R]evolution in Clinical Laboratories: participating laboratories measure calibrators. The outcome of these measurements is used to calculate conversion factors. The obtained factors are subsequently applied to standardize the results of a number of routine chemistry parameters. This conversion method is now part of a quality system to collect clinical laboratory data in accordance with the Good Clinical Practice guidelines on patients participating in clinical trials organized by the pharmaceutical industry. This approach eliminates the need for centralized laboratory services. Presently over 300 laboratories participate in a number of pan-European clinical trials where the VCL is applied. In this paper our experiences over the last 2 years will be discussed.
Keywords: Key words Virtual Central Laboratory; Analytical standardization; Good clinical practice; Database management
Blood banking quality: minimum requirements for TQM by Jean Claude Libeer (pp. 436-438).
In 1995, the Council of Europe published a guide with recommendations providing transfusion services with a set of guidelines and principles relating to the preparation, use and quality assurance of blood components. As a blood transfusion service is at the same time a supplier of blood products and a test laboratory the quality management system must include good medical practice, good manufacturing practice and good laboratory service, all of which are closely linked. We made a critical evaluation of the content of the guide and analysed requirements and recommendations in comparison with quality management systems applied by the concerned partners. As a major critic we observed that the guide does not take into account any quality system of the in vitro diagnostic (IVD) supplier and/or distributor. With the addition of some items outlined in ISO 25 and ISO 9000, the Council of Europe document can be improved so that it complies with internationally accepted quality management standard recommendations.
Keywords: Key words Blood bank; Quality management; Blood products; Laboratory tests; TQM
Workflow management: changing your organization through simulation by G. G. van Merode; Siebren Groothuis; Henk J. M. Goldschmidt (pp. 438-442).
This paper discusses first performance measures for clinical laboratories. In order to realize a required performance, workflow management is essential. The use of discrete event simulation is discussed with regard to analysing and designing a workflow management system. This is illustrated by a simple example.
Keywords: Key words Workflow management; Scenario analysis; Change management; Performance measures; Quality indicators; Turnaround time; Capacity planning
Standardization of quality management in the medical laboratory by Keith Shinton (pp. 442-445).
A new ISO standard (ISO/DIS 15189) on quality management in the medical laboratory is being prepared. The origins and development of this in ISO and the interaction by CEN in Europe is presented. The major comments already received are given as well as the likely progress of this ISO standard. Once published it will have implications for accreditation of medical laboratories throughout the world and particularly those in Europe.
Keywords: Key words Quality; Management; Medical; Laboratory