球团矿检测能力验证结果分析

为了了解我国铁矿类商品尤其是球团矿检测的水平,国家认监委于2010年实施了球团矿检测的能力验证计划.该能力验证共有来自20个省市39家实验室参加,包括出入境检验检疫系统、地矿实验室、冶金实验室.能力验证项目主要考察全铁和硫含量的检测能力,推荐用GB/T 6730.5和GB/T 6730.61两个标准进行检测,对实验室的...     

Bootstrap方法在能力验证统计分析中的应用北大核心CSCD

由于经济全球化和高科技迅猛发展的需要,我国许多实验室已通过了中国合格评定国家认可委员会（CNAS）的认可,还有许多实验室正在准备认可。在实验室认可活动中利用实验室间比对的能力验证活动是一项非常重要的内容,它受到国际实验室认可合作组织及世界各国实验室认可组织的高度重视。能力验证是利用实验室间的比对来判定实验室和检查机构能力的活动[1-2],     

Bootstrap方法在能力验证统计分析中的应用

<正>由于经济全球化和高科技迅猛发展的需要,我国许多实验室已通过了中国合格评定国家认可委员会(CNAS)的认可,还有许多实验室正在准备认可。在实验室认可活动中利用实验室间比对的能力验证活动是一项非常重要的内容,它受到国际实验室认可合作组织及世界各国实验室认可组织的高度重视。能力验证是利用实验室间的比对来判定实验室和检查机构能力的活动[1-2],也是认可机构加入和维     

利用能力验证结果评价参加实验室的整体检测能力

能力验证是利用实验室间比对确定实验室检测能力的活动,其评价结果多用于评估单个实验室的检测能力。行业监管部门期望掌握实验室整体能力和检测方法的相关信息,为分析参加实验室的整体检测能力和不同测试方法的差异,分析了3年航空煤油检测能力验证结果,采用满意结果百分比、|Z|值平均值随参加能力验证次数的变动情况,证实了能力验证对整体检测能力的改进作用;利用异方差t检验,比较不同测试方法结果的一致性和精密度差异;通过比较能力验证评价标准差和检测标准的精密度要求,评价参加实验室整体检测能力是否符合检测标准要求。研究表明,能力验证数据能够用于定量分析参加实验室的整体检测能力,为行业实验室监管和检测方法间比对提供依据。     

基于迭代算法A的海水盐度能力验证结果分析

为评价海洋检验检测机构海水盐度检测能力,国家海洋标准计量中心设计并实施了2020年度海水盐度能力验证计划,制备能力验证样品并开展均匀性检验。本次能力验证采用双样品以随机组合形式发放,利用迭代算法A对62家实验室提交的能力验证数据进行统计分析处理,合理确定指定值及其不确定度,将能力验证数据转化为能力统计量,根据Z比分数评定各参加实验室能力验证结果。结果显示,双样品全部“满意”的实验室有52家,占85.5%,有3家实验室能力验证结果“不满意”,6家实验室能力验证结果“有问题”。“不满意”和“有问题”的实验室共占14.5%。本次能力验证数据的频率分布接近正态分布,通过开展双样品联合置信概率分析和仪器类型统计分析,与往年能力验证结果“满意率”进行比较,绝大多数实验室海水盐度检测能力良好,个别实验室仍需加强海水盐度检测能力建设和内部质量控制。     

稳健统计技术及其在实验室能力验证数据处理中的应用

介绍了传统统计方法存在的问题及稳健统计技术的发展历史、稳健统计技术的属性、基本假设模型、稳健统计量及在实验室能力验证数据处理中的具体应用,提出了实验室能力验证的评价标准。     

置信椭圆在能力验证中的应用

能力验证是判断和监控检测/校准实验室能力的有效手段,同时也是评价实验室技术能力的重要依据之一。为更好地考核实验室技术能力,能力验证样品通常设计成分割水平样品,即组织者为每个参加能力验证的实验室提供两份目标值水平略有差     

简讯

我国逾2万家实验室已获资质认定不久前,国家认监委在京召开了2006年能力验证工作总结暨2007年能力验证工作布置会议。迄今为止,全国获得实验室资质认定证书的实验室共有22576家,其中,国家级2259家,省级20317家,获得国家产品质检中心授权的机构331家。近年来,国家认监委不断加大     

水中易释放氰化物能力验证样品的研制及应用

根据国家地表水环境质量监测网监测任务要求和环境监测的实际需要,制备了水中易释放氰化物能力验证样品。通过均匀性、稳定性检验以及量值一致性评价,研制的样品均匀性良好,在3℃~6℃冷藏避光保存条件下1年内稳定,样品配制值与多家实验室协作测定结果一致。探讨了样品在能力验证活动中的应用,共有来自全国11个省的32家实验室参加了水中易释放氰化物的能力验证计划,实验室满意率在80%以上,实验室结果出现有问题或不满意主要是由于样品前处理以及检测过程质量控制不当导致的。经检测及实验室反馈的数据验证,该能力验证样品能够应用于能力验证活动。     

两种稳健统计法在石油产品能力验证结果分析中的比较北大核心CSCD

能力验证是国际通行的实验室检测能力评价手段,是实验室质量管理常用和有效的一种手段^[1]。按照实验室认可评审和资质认定的相关要求,实验室对检测能力附表中各领域均应按一定频次参加有资质单位组织的能力验证活动,从而满足监管机构的要求,确认实验室的管理能力,识别检测过程中的问题等,使管理体系有效运转,提升实验室自身检测能力。     

氧指数检测能力验证结果分析

为了解氧指数检测实验室的能力水平,中国合格评定国家认可委员会(CNAS)开展了"塑料燃烧性能试验(氧指数法)"能力验证计划。通过对氧指数能力验证计划的结果进行统计分析,评价了氧指数检测实验室的整体水平,指出了氧指数检测实验室普遍存在的几类问题并提出了相应的建议。     

实验室熟练水平测试方案简介

介绍了实验室熟练水平测试方案(LPTS)的目的,类型,以及实验室熟练水平测试的组织、基本运行程序和实施的具体步骤。     

土壤中重金属元素检测的质量认证

探讨了土壤中重金属检测能力验证的质量控制措施,为确保能力验证结果的准确性及不断提高实验室的检测技术水平提供参考.     

利用实验室间国际比对验证15N丰度的测定能力

参加了由FAO／IAEA组合的全氮和^15N丰度检测能力验证的实验室国际间的比对两年的比对结果表明,我们实验室对3个植株样品全氮和^15N丰度的测定值与指定值十分吻合,检测结果准确,此项计划的实施,证明了本实验室的检测能力和国际实验室间的水平。     

Proficiency testing in analytical laboratories: how to make it work

 This paper covers the role of proficiency testing schemes in providing an occasional but objective means of assessing and documenting the reliability of the data produced by a laboratory, and in encouraging the production of data that are "fit-for-purpose". A number of aspects of proficiency testing are examined in order to highlight features critical for their successful implementation. Aspects that are considered are: accreditation, the economics and scope of proficiency testing schemes, methods of scoring, assigned values, the target value of standard deviation σ_p, the homogeneity of the distributed material, proficiency testing in relation to other quality assurance measures and whether proficiency testing is effective. Stress is placed on the importance of any proficiency testing scheme adhering to a protocol that is recognised, preferably internationally. It is also important that the results from the scheme are transparent to both participating laboratory and its "customer". Received: 03 November 1995 Accepted: 20 November 1995     

Harmonization and transferability of performance assessment: experience from four serum aluminum proficiency testing schemes

Proficiency testing schemes monitor laboratory performance and provide a stimulus for improvement in accuracy. Where several schemes operate in the same analytical sector, there are risks that assessments of performance may be in conflict. Performance assessment for the determination of trace elements such as aluminum in serum is particularly important due to the high risk of contamination and therefore erroneous results. The objectives of this work were (1) to compare several mathematical models to establish a predefined standard deviation for proficiency assessment and (2) to evaluate the influence of instrumental methods and proficiency testing scheme on the assessment of performance for serum aluminum measurements. For this purpose, three samples were sent to the participants of four proficiency testing schemes. Assigned values were calculated according to algorithm A according to ISO 13528 and standard deviation for proficiency assessment according to three methods based on individual variability, state of the art or previous proficiency testing results. The method based on individual variability produced a more stringent standard deviation compared to analytical imprecision based on the state of the art. The instrumental methods gave similar results, whereas significant differences were observed between the four proficiency testing schemes indicating that harmonization of the standard deviation for proficiency assessment fails to allow transferability from one proficiency testing scheme to another and that additional factor(s) contribute to variability in performance assessment.     

Regular participation in proficiency testing provides long term improvements in laboratory performance: an assessment of data over time

Data from various proficiency testing schemes, operated by LGC Standards, was collated and reviewed to determine whether regular involvement within third party, proficiency testing, either over a prolonged period of time or via multiple participation, had improved the performance of those laboratories taking part. Three statistical evaluations were applied to historical PT results, a review of improvements over time, demonstrated by the evaluation of satisfactory performance scores achieved, a review of the relative robust standard deviations obtained from multiple methods and a focused review of one analyst participating in proficiency testing over a prolonged period of time. In each case the data indicated that long term participation and evaluation via proficiency testing had resulted in consistent and sustained improvements in laboratory performance.     

The current status and future of medical laboratory quality regulation and accreditation in Ghana

High-quality and reliable laboratory services are important components of effective and well-functioning health systems. Accurate, reliable and timely medical laboratory testing is crucial to patient care and disease surveillance. Unfortunately, in many sub-Saharan African countries, medical laboratory systems are adversely affected by the unavailability of medical laboratories, poor laboratory infrastructure and lack of well-trained personnel [1]. Quality in the laboratory is only achieved in a systematic way through the implementation of a quality management system. The results of the study showed that approximately 60?% of the 78 respondents were unaware of the requirements of ISO 15189:2007. A trial of proficiency testing, termed ??blind proficiency testing??, was carried out in which 19 laboratories determined the concentrations of urea and cholesterol in a proficiency testing material. Of the 19 laboratories that determined the concentration of urea, 63?% produced satisfactory results with scores between ?2 and +2. Similarly, 63?% of the participating laboratories obtained satisfactory z scores for cholesterol determination. Some of the laboratories that obtained satisfactory scores for urea determination had unsatisfactory scores for cholesterol determination and vice versa. It is recommended that the Ghanaian government pass a law and establish a standard to regulate medical laboratories in Ghana in order to improve quality in a significant way.     

Quality issues in proficiency testing

 Proficiency testing is a means of assessing the ability of laboratories to competently perform specific tests and/or measurements. It supplements a laboratory's own internal quality control procedure by providing an additional external audit of their testing capability and provides laboratories with a sound basis for continuous improvement. It is also a means towards achieving comparability of measurement between laboratories. Participation is one of the few ways in which a laboratory can compare its performance with that of other laboratories. Good performance in proficiency testing schemes provides independent evidence and hence reassurance to the laboratory and its clients that its procedures, test methods and other laboratory operations are under control. For test results to have any credibility, they must be traceable to a standard of measurement, preferably in terms of SI units, and must be accompanied by a statement of uncertainty. Analytical chemists are coming to realise that this is just as true in their field as it is for physical measurements, and applies equally to proficiency testing results and laboratory test reports. Recent approaches toward ensuring the quality and comparability of proficiency testing schemes and the means of evaluating proficiency test results are described. These have led to the drafting of guidelines and subsequently to the development of international requirements for the competence of scheme providers. Received: 2 January 1999 · Accepted: 7 April 1999