Back to Search Start Over

Trend detection with non-detects in long-term monitoring, a mixed model approach.

Authors :
Sköld, Martin
Source :
Environmental Monitoring & Assessment; Jun2023, Vol. 195 Issue 6, p1-11, 11p
Publication Year :
2023

Abstract

In long-term monitoring of contaminants in biota, a common approach is to use yearly geometric means of measured concentrations in sampled individuals as a basis for trend analysis. When some or all measurements in a particular year are reported as non-detects, it is unclear how to proceed in calculating the yearly mean. I argue that by casting the problem in terms of a mixed model, non-detects can be accounted for using statistical techniques for censored data. The approach is illustrated using data from the Swedish national monitoring programme for contaminants in biota. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
01676369
Volume :
195
Issue :
6
Database :
Complementary Index
Journal :
Environmental Monitoring & Assessment
Publication Type :
Academic Journal
Accession number :
164356362
Full Text :
https://doi.org/10.1007/s10661-023-11285-8