Screening is investigating the chemical or biological composition of a sample, without making any assumptions about the expected result. An important condition for effective screening is that screening methods include non-specific data, whereby the trick is to miss as few substances as possible. The ultimate added value is to subsequently extract relevant information from screening data using data analysis techniques.
With screening you exchange certainty for a stronger increase in the analysis range. Screening techniques, such as liquid and/or gas chromatography coupled with mass spectrometry, are important because they can capture a very broad measuring range in one analysis. Screening often has less certainty than targeted method analysis, especially because there is a chance of false-negative and false-positive results.
Screening makes it possible to identify new chemical substances and to set up a safety net for high-risk substances. It is therefore a technology which focuses on the future. In addition, screening data is retrospective: with today's insight, you can look back at data from the past. This allows you to search for a (new) chemical substance found today in data from recent years.
More information: Houtman et al. https://doi.org/10.1016/j.scitotenv.2019.133806]