Journal Article Epublish
PubMed: 42948457 DOI: 10.2903/j.efsa.2026.10391
Guidance on default values and uncertainty factors to be used by the EFSA Scientific Committee, Scientific Panels and Units in the absence of actual measured data.
EFSA J 24(10):e10391
Authors: Susanne Hougaard Bennekou, Ana Allende, Angela Bearth, Josep Casacuberta, Laurence Castle, Tamara Coja, Amélie Crépet, Thorhallur Halldorsson, Laurentius Ron Hoogenboom, Pikka Jokelainen, Helle Knutsen, Claude Lambré, Søren Nielsen, Dominique Turck, Antonio Vicent Civera, Roberto Edoardo Villa, Holger Zorn, Kyriaki Machera, Josef Schlatter, Maria Anastassiadou, Dayana Buzle, Agnès De Sesmaisons-Lecarrè, Jean-Lou Dorne, Petra Gergelová
Abstract
The European Food Safety Authority (EFSA) has updated its 2012 guidance on selected default values (DVs) to be used by the EFSA Scientific Committee (SC), Scientific Panels and Units in the absence of actual measured data. DVs are meant to be typical values, being not necessarily conservative, while uncertainty factors (UFs) tend to be conservative. Examples of DVs are for body weights of humans or animal species, food and feed intake, or conversion factors for chemical substance concentration in feed or drinking water into daily doses in experimental animal studies. UFs are used to account for uncertainties in the assessment e.g. regarding inter/intra-species extrapolation, extrapolation for duration of exposure or for deficiencies in the database. The SC assessed the scientific basis for the DVs and UFs used by EFSA Units/Panels, considering published literature and the evidence derived from the available scientific databases. Most of the proposed values in the 2012 SC guidance and the rules for rounding of derived values were retained, while some DVs had become obsolete. The main changes concern newly added DVs and the updated scientific rationale for a number of the existing DVs and UFs. Regarding the UF of 100 for inter/intra-species extrapolation, the SC recommends that EFSA convenes an international expert group to evaluate the basis of the UF of 100 and its sub-factors for inter/intra-species extrapolation. In addition, the use of probabilistic approaches should be investigated. The SC reiterates that, whenever specific robust and reliable data are available, these should be used instead of DVs. The aim of this guidance document is not standardisation but harmonisation. It is always possible to deviate from the proposed DVs and UFs, provided that the rationale for such deviation is described.
MeSH
Absenteeism, Uncertainty, Body Weight