[National Antimicrobial Resistance Surveillance System (NAMRSS) external quality assessment studies: 2011-2016]. / Ulusal Antimikrobiyal Direnç Sürveyans Sistemi (UAMDSS) Dis Kalite Degerlendirme Çalismalari: 2011-2016.

Establishment of sustainable and evidence-based surveillance systems are recommended for prevention of microbial resistance by the World Health Organization (WHO). As a necessity of these surveillance systems, participants are recommended to implement an external quality assessment (EQA) program. In this scope, National Antimicrobial Resistance Surveillance System (NARSS) has been established within the Public Health Institute of Turkey (PHIT) in our country since 2011. In the scope of this surveillance, NARSS EQA program has been implemented in a cycle per year and four isolates were sent to participants per cycle every year since 2011. In this study, it was aimed to evaluate the six years results of the EQA programs being implemented on NARSS participants between 2011 and 2016. The surveillance system consisted of 118 laboratories. Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pneumoniae, Enterococcus faecium/faecalis and Acinetobacter baumannii bacteria included in scope of the surveillance were sent to participants. Identification of bacteria to the species level, verification of the antibiotic susceptibility test results and existence of specified resistance of the isolates performed with valid test methods required from the participants. Identified isolates were cultured with routine microbiological methods and sent to participants in ambient temperature in triple carrying pouches inside suitable carrying media via PTT Cargo. The results were entered by means of passwords prepared by PHIT and sent to the web based system. The analysis of results were made with SPSS program. A total of twenty-three isolates were sent to participants between 2011 and 2016. It was determined that participants commonly preferred automated systems for bacterial identification and antibiotic sensitivity test results. The use of MALDI TOF MS system was determined to be raised up to 15.65% in 2016. It has been determined that usually little mistakes were done in bacterial identification but the error rate was high especially in antimicrobial susceptibility test results with close clinical threshold values. Although not required for antibiotic susceptibility test results, it was determined that phenotypic tests have been used more widely in determining the specific resistance mechanisms that are important for epidemiological data. It was determined that 80% of participants have used EUCAST standards in 2016. As a result of this research, we have observed that EQA studies of NARSS EQA are a good performance tool for sustainable and evidence based surveillance studies, that the national antimicrobial resistance data quality is sufficiently good and that the data can be shared on international platforms. In addition, the regular maintenance of national surveillance studies shown that laboratories have positive reflections on self improvement in achieving up to date and accurate results.