Is everything wrong in analytical chemistry? A study on reproducibility

Reproducibility in science, particularly in fields that develop and apply analytical methods, such as analytical chemistry and related disciplines, has been increasingly questioned. A survey by Monya Baker (2016) indicated that most researchers acknowledge a reproducibility crisis. Frequently cited causes include low statistical power or poor analysis, insufficient replication in the original laboratory, unavailability of methods, poor experimental design, and absence of raw data. Chemistry was the field in which researchers most frequently reported difficulty reproducing both their own and others’ experiments. This study was conducted to confirm the existence of this crisis in analytical methods, quantify its extent, and evaluate its relationship with method validation and measurement uncertainty, which are based on statistical approaches and metrological principles, using the Analytical Quality Assurance Cycle. The results suggest that the crisis is directly associated with incorrect statistical procedures, inadequate validation criteria, and deficient execution of performance characteristics, factors that directly contribute to elevated measurement uncertainty. In 28% of the evaluated methods, expanded uncertainties exceeded 100% at the first point of the linearity assessment, compromising both result reliability and metrological traceability. These observations support concerns from previous studies regarding statistical errors, insufficient replication, and limited methodological transparency. Enhancing statistical training and quality assurance in academic programs, broader adoption of open science practices, and clearer policies aligned with international guidelines, such as EURACHEM, ISO/IEC 17025, and the OECD Principles of Good Laboratory Practice, may improve the reproducibility and reliability of analytical research.