Under EC Regulation No. 1107/2009, binary criteria are used to categorize substances by comparing the properties of the compound to simple threshold or trigger values.
In the SRC task, participants are required to categorize substance-related and control pictures by moving a manikin figure either toward or away from the picture.
Pharmacological treatments were categorized into substance classes, while usual care and placebo treatment were considered as reasonably comparable reference treatments (for example, supported by [ 5]).
Diagnoses were categorized into substance use disorders, post-traumatic stress disorder, other anxiety disorders, depressive disorders, and bipolar or psychotic disorders.
Events that involved chemicals from more than one substance category were categorized as "multiple substances".
Tobacco smoke is a heterogeneous mixture that contains approximately 4,000 chemical compounds, including 40 substances categorized as carcinogenic to humans or animals [ 44].
We further categorized number of substances used as increased when a person reported a higher number at the second enrollment, compared to the first enrollment; decreased when a person reported a lower number at second enrollment compared to first enrollment, and; no change when the number of substances used stayed the same.
Falsely categorizing a substance as positive or negative due to specific characteristics of the tested cells is always a risk in cytotoxicity screens.
It follows that clinical investigations of products or substances regulated as "foods" and "dietary supplements" are not subject to the rigors of the IND process unless the intended use or endpoint(s) investigated serve to also categorize the substance as a "drug" and "new drug" or "biological product".
It may be that individuals categorized as having "substance abuse" had less risk of PDO than people who would be categorized as having an "SUD".
