Abstract
Background: External quality assessment (EQA), including proficiency testing (PT), is a fundamental aspect of laboratory quality management and a key requirement for diagnostic laboratory accreditation. Summary: This review highlights significant gaps in comprehensive EQA/PT programs for diagnostic non-gynecological cytopathology that fully address all aspects of the diagnostic process, particularly in Europe. Key Messages: Current EQA/PT programs for diagnostic cytopathology are mostly regional, national, and only partially cover the examination process. The unique challenges of diagnostic cytopathology, including small and limited patient samples, non-standardized laboratory procedures, biomarker testing tailored to specific cytology samples, and the qualitative subjective nature of cytopathologic reporting, necessitate adapted approaches for effective and meaningful EQA.
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