EXTERNAL QUALITY ASSESSMENT PROGRAMS: PAST, PRESENT AND FUTURE

Summary: External Quality Assurance (EQA) and Proficiency Testing (PT) programs are fundamental tools for quality evaluation and improvement in clinical laboratories. A growing body of evidence has been collected to demonstrate the usefulness of these programs for reducing inter-laboratory variation, analytical errors and for improving the »state-of-the art«. The validity of EQA/PT programs is strongly affected by the quality of control materials, the design of the program, namely the ability to estimate analytical bias and imprecision, and the commitment of providers to assist in the education participant laboratories. Future perspectives of EQA/PT are the possibility to evaluate pre- and post-analytical steps, the utilisation of Internet for receiving and communicating results to participant laboratories and the accreditation/certification of the programs.