Minimum Performance Specifications Research Articles

Evaluation laboratory prenatal screening performance based on biological variation of risk assessment in second trimester in China

Abstract Objectives This study intends to evaluate prenatal screening risk assessment performance based on biological variation to help clinical laboratories realize their own screening performance and set the appropriate performance specifications for prenatal screening risk assessment in China. Methods Fifteen samples with detailed clinical information were distributed to participants and the prenatal screening Down syndrome risk assessment of each sample were submitted. Three levels of performance specification (optimum, desirable, minimum) derived from biological variation were used to evaluate laboratory prenatal screening risk assessment performance. Results A total of 797 laboratories participated in the survey project. There are 216 laboratories using serological double-marker test and 581 laboratories using serological triple-marker test. For each screening protocol, more than 92.00% laboratories meet minimum performance specifications, more than 84.00% laboratories meet desirable performance specifications, and only about 62.50%laboratories meet optimum performance specifications. The Feltz and Miller test indicated that there were no significant statistical differences in the RCV for double-marker screening in 5 platforms and triple-marker screening in 6 platforms. Conclusions The risk assessment of prenatal screening in the second trimester in China can be improved further. It is appropriate to choose desirable performance specifications for external quality assurance organizations to evaluate the risk assessment performance.

Analytical performance of 17 general chemistry analytes across countries and across manufacturers in the INPUtS project of EQA organizers in Italy, the Netherlands, Portugal, United Kingdom and Spain.

Optimum patient care in relation to laboratory medicine is achieved when results of laboratory tests are equivalent, irrespective of the analytical platform used or the country where the laboratory is located. Standardization and harmonization minimize differences and the success of efforts to achieve this can be monitored with international category 1 external quality assessment (EQA) programs. An EQA project with commutable samples, targeted with reference measurement procedures (RMPs) was organized by EQA institutes in Italy, the Netherlands, Portugal, UK, and Spain. Results of 17 general chemistry analytes were evaluated across countries and across manufacturers according to performance specifications derived from biological variation (BV). For K, uric acid, glucose, cholesterol and high-density density (HDL) cholesterol, the minimum performance specification was met in all countries and by all manufacturers. For Na, Cl, and Ca, the minimum performance specifications were met by none of the countries and manufacturers. For enzymes, the situation was complicated, as standardization of results of enzymes toward RMPs was still not achieved in 20% of the laboratories and questionable in the remaining 80%. The overall performance of the measurement of 17 general chemistry analytes in European medical laboratories met the minimum performance specifications. In this general picture, there were no significant differences per country and no significant differences per manufacturer. There were major differences between the analytes. There were six analytes for which the minimum quality specifications were not met and manufacturers should improve their performance for these analytes. Standardization of results of enzymes requires ongoing efforts.

Energy savings assessment for digital-to-analog converter boxes

The Digital Television (DTV) Converter Box Coupon Program was administered by the U.S. government to subsidize purchases of digital-to-analog converter boxes, with up to two $40 coupons for each eligible household. In order to qualify as Coupon Eligible Converter Boxes (CECBs), these devices had to meet a number of minimum performance specifications, including energy efficiency standards. The Energy Star Program also established voluntary energy efficiency specifications that are more stringent than the CECB requirements. In this study, we measured the power and energy consumptions for a sample of 12 CECBs (including 6 Energy Star labeled models) in-use in homes and estimated aggregate energy savings produced by the energy efficiency policies. Based on the 35 million coupons redeemed through the end of the program, our analysis indicates that between 2500 and 3700GWh per year are saved as a result of the energy efficiency policies implemented on digital-to-analog converter boxes. The energy savings generated are equivalent to the annual electricity use of 280,000 average US homes.

Programmable instrumentation for high repetition rate experiments providing control in real time and acquisition of a train of pulses

An automated, low-cost programmable instrumentation system which solves many of the problems associated with the data acquisition and control of high repetition rate experiments is described. The system can monitor and control experiments on a pulse-by-pulse basis while digitally storing consecutive pulses which occur in the train. The system compares well with manual test equipment and commercial transient diagnostic systems which cannot provide the high-speed control and data acquisition available here. The oscilloscope used to store the train of pulses can digitize at a maximum rate of 100 MHz, and has 32 kbytes of acquisition memory that can be subdivided into a sequence of as many as 250 separate segments. In order to reduce the system software reinitialization time to acquire each successive sequence within the total train, a novel IEEE-488 compatible microprocessor system is used in conjunction with a host personal computer. The microprocessor controls triggering of the experimental equipment based on digitally acquired waveform information. This information is also used to coordinate the reinitialization of the oscilloscope by the host computer. The system can acquire each and every pulse at repetition rates up to 40 Hz. Above this rate, the probability of acquiring a particular pulse in the train falls slightly below unity due to the finite time required to reinitialize the oscilloscope. The maximum synchronously controllable pulse repetition rate of the microprocessor is 20 000 Hz. Minimum performance specifications are provided which are significantly better than other approaches. The system is employed in high-voltage, dielectric breakdown experiments. For the example given, there are 62 segments in the acquired sequence, with a 100-MHz digitizing rate during the 5-μs acquisition time for each segment. The breakdown pulse in the train and as many as 61 pulses preceding it are obtained.

Technical Performance of Community Antenna Television Systems

There is a growing interest in technical performance specifications for Community Antenna Television (CATV) systems on the part of system operators, manufacturers, and governmental regulatory bodies. There is at present no accepted standard for such operations. This paper outlines the major elements involved in adequate specifications. Numerical performance standards are suggested in some cases; in others, more work appears necessary to develop suitable measuring techniques and to determine the correlation between subjective evaluation of picture quality and measurable video signal characteristics. An Appendix provides a concise tabulation of suggested minimum performance specifications.

The Xth Plenary Assembly of the CCIR

The paper is based on a lecture given to the IEE Electronics Division on 10th April 1963 and outlines some of the more important results achieved by the Xth Plenary Assembly of the CCIR held at Geneva from the 16th January to 15th February 1963.As a preliminary, the organisation and functions of the International Telecommunication Union (ITU), an agency of the United Nations, are briefly considered, and the role of the CCIR in studying technical and operating questions in the radio field and making recommendations to the ITU is explained.Some of the more important results achieved by the Xth Plenary Assembly through its 14 Study Groups, which cover the whole radio field, are summarised. In particular, the work of Study Group IV which deals with space systems is examined in some detail, and the major technical contributions being made by this Group, which was set up only some four years ago, are emphasised. Many of the technical recommendations already made will have a major influence on the Extraordinary Administrative Radio Conference to be held at Geneva in the latter part of 1963. The tasks of this conference will include the provision of frequency allocations for operational communication systems employing artificial earth satellites as relays.Another aspect of the work of the Xth Plenary Assembly is in the field of technical assistance to under-developed countries. In this connection a study was made of the minimum performance specifications required for low-cost broadcasting receivers suitable for large-scale production; the object being to place within the range of the populations of new and developing countries, simple and robust broadcasting receivers of low cost. Specifications were prepared for three types of set: m.f., m.f./h.f. and v.h.f. receivers.As indicated in the paper, the Xth Plenary Assembly was an unqualified success and the technical recommendations, of which 101 were made, will assist in, and influence, the development of radio-communication systems.