About estimating the limit of detection by the signal to noise approach

The limit of detection (LOD) is an important figure of merit estimated in validation studies or when reporting the performances of an analytical method. While the very meaning of LOD is clear to anyone, its estimation is still matter of discussion. This explains the plethora of available approaches. However, the most popular are generally the simplest ones. Between these, it is worth mentioning the approach based on the signal to noise (S/N) ratio, included among those suggested by international guidelines such asthe United States Pharmacopeia, the European Pharmacopoeia and others. This contribution attempts evaluating if this approach could be replaced by that based on the standard error of estimate, sy/x.