Analysis of Nonconformities to ISO/IEC 17025:2017 Laboratory Accreditation, Comparing Pre- and Post- Accreditation Audit in 2021 and 2023

Nonconformities of ISO/IEC 17025:2017 Comparing Pre- and Post-Accreditation

Abstract

         This study aimed to analyze the number and types of nonconformities (NCs) identified in public health testing laboratories based on the ISO/IEC 17025:2017 standard, which have applied for laboratory accreditation from the Bureau of Laboratory Quality Standards, Department of Medical Sciences, Thailand. It compared the assessment results before accreditation in 2021 with the surveillance assessment results in 2023. The study utilized secondary data from assessment reports of 138 laboratories, consisting of 37 public health laboratories and 101 private sector laboratories. The data were analyzed according to the requirements of ISO/IEC 17025:2017, including Clause 4 (General requirements), Clause 5 (Structural requirements), Clause 6 (Resource requirements), Clause 7 (Process requirements), and Clause 8 (Management system requirements). The results indicated that the total number of nonconformities (total NCs) and major nonconformities (major NCs) significantly decreased after accreditation (X² = 19.487, p < 0.001 and X² = 9.635, p = 0.047, respectively). The most frequently observed nonconformities were related to process requirements (Clause 7). These results suggest that the accreditation mechanism effectively enhances laboratory quality, promotes continual improvement aligned with international standards, and reduces the occurrence of nonconformities that may compromise the accuracy and reliability of test results. The role of accreditation bodies and ongoing surveillance assessments is crucial in maintaining quality standards and ensuring the sustainable development of testing laboratories in Thailand.