Four years on, what is the SCENTinel screening tool is teaching us about smell disorders?

First, there was SCENTinel 1.0, then 1.1, and now 2.

1—the different iterations of the rapid screening tool for detecting new-onset loss of smell developed by scientists at the Monell Chemical Senses Center. Since its launch in late 2020, several studies have validated its accuracy in detecting smell dysfunction and value as a tool for testing in large populations of people. SCENTinel is now the heart of an international campaign—led by Monell—to make smell testing a routine part of general wellness checks with primary care physicians, as well as a screening tool for viral outbreaks such as COVID-19 or early smell loss associated with Parkinson's disease and related disorders.

In addition, it has been patented and licensed to Ahersla Health for commercial use. The COVID-19 pandemic showed sensory scientists the need for a quick, inexpensive, easy-to-use way to screen for smell disorders. The SCENTinel test card contains two blank labels and one with an odor.

The user detects which label has the odor, rates its intensity, identifies the odor's name from a list of visual choices, and rates its pleasantness. The first three tasks provide an overall pass/fail score for smell function; pleasantness informs the potential of having a distorted sense of smell called parosmia. The first version (SCENTinel1.

0) had only one odor option: flower. SCENTinel 1.1 has four options: flower, coffee, bubblegum, and caramel popcorn, and the current version, SCENTinel 2.

1, has nine options: f.