Jenny R W
New York State Department of Health, Wadsworth Center for Laboratories and Research, Albany 12201-0509.
Clin Chem. 1994 May;40(5):723-8.
Participation in a proficiency testing (PT) program is a valuable adjunct to laboratory activities dedicated to the maintenance of reliable analytical methods. The PT program may facilitate continuous quality improvement if laboratory performance is presented in the context of expectations espoused by healthcare professionals for optimal patient care. Statistical process control (SPC) and capability analysis are tools used by industry in a Total Quality Management environment to characterize and monitor the performance of its processes relative to performance specifications. I conceptualized the use of an analytical system by many laboratories as a process that periodically produces results from the analysis of PT specimens. I treated a set of five PT results (theophylline) reported by a laboratory as a process sample and subjected the samples collected from many laboratories to SPC and capability analysis. The control charts--mean-(X-bar) and s-charts--produced by the analysis readily identify significant analytical errors in the context of peer performance and performance specifications provided by the regulatory program and analytical goal setting. The capability index (desirable Cp > 1.0) determined from clinical specification limits for the three analytical systems evaluated suggests an opportunity for improvement of laboratory performance.
参加能力验证（PT）计划是致力于维持可靠分析方法的实验室活动的一项重要辅助措施。如果将实验室性能置于医疗专业人员为实现最佳患者护理所秉持的期望背景下，PT计划可能有助于持续质量改进。统计过程控制（SPC）和能力分析是行业在全面质量管理环境中用于根据性能规范来表征和监控其过程性能的工具。我将众多实验室使用分析系统的过程概念化为一个定期对PT标本进行分析并产生结果的过程。我把某个实验室报告的一组五次PT结果（茶碱）视为一个过程样本，并对从众多实验室收集的样本进行SPC和能力分析。分析所生成的控制图——均值（X-bar）图和标准差（s）图——能在同行性能以及监管计划和分析目标设定所提供的性能规范背景下轻松识别出重大分析误差。根据所评估的三个分析系统的临床规范限度确定的能力指数（理想情况下Cp > 1.0）表明实验室性能有改进的空间。
