At the recent 10th Conference on Chemometrics, Metrology and Artificial Intelligence in Analytics conference in Poznań, Ivo Leito presented a keynote talk titled Estimating measurement uncertainty in chemical measurements: difficulties and misconceptions.
The presentation outlined three important misconceptions in estimation of measurement uncertainty in chemical measurements: (1) Uncertainty is primarily determined by the accuracy of the instrument; (2) Uncertainty is quantitatively expressed by (dis)agreement between results of repeated measurements and (3) „Simple“ measurements are simple.
All three misconceptions were debunked during the talk on the basis of the research of our group from the recent years: (1) In chemistry, uncertainty mostly comes from the object, not from the instrument; (2) In chemistry, uncertainty usually comes mainly from systematic effects, not from (within-day) random effects and (3) In chemistry, even for „simple“ measurement, adequate modeling and evaluation of individual uncertainty components is usually challenging.
The presentation made use of the recent work of our group: S. Pawade et al “A quantitative approach to determine water and moisture content of different types of lignin using attenuated total reflectance Fourier transform infrared spectroscopy combined with partial least squares regression” Biofuels, Bioprod. Bioref. 2026; L. Sooväli et al “Uncertainty sources in UV-Vis spectrophotometric measurement” Accred. Qual. Assur. 2006, 11, 246-255; “Critical compilation of acid pKa values in polar aprotic solvents” Pure and Applied Chemistry, 2025, 97, 973-998; I. Helm et al “Comparative validation of amperometric and optical analyzers of dissolved oxygen: a case study” Environ. Monit. Assess. 2018, 190.
The presentation presented a pragmatic solution to measurement uncertainty evaluation of chemical measurement results: the approach based on validation and quality control data (also known as the single-lab validation approach).
The presentation was warmly received by the participants, receiving a number of quations and coffee break discussions!
(This research presented in the talk has been supported by the IUPAC project 2015-020-2-500, MetPart 23RPT03 GrainMet, Estonian Ministry of Education and Research (TK210), Estonian Research Council grants IUT20-14, PRG690 and PRG1557, Estonian Center of Analytical Chemistry, www.akki.ee)