Which of the following best describes the term "substance use disorder severity"?

The term "substance use disorder severity" is best described by evaluating the impact of substance use on daily functioning. This definition focuses on how substance use disrupts various aspects of a person's life, including personal responsibilities, social interactions, and overall well-being. The severity of a substance use disorder is often assessed by determining the extent to which the individual’s substance use leads to significant impairment or distress in these areas.

While other factors such as the frequency of use, duration, and types of substances can provide context about the individual's situation, they do not capture the overall impact and challenges faced by the individual in their daily life. Thus, understanding severity through the lens of functioning gives a comprehensive view of how substance use disorder affects a person's daily activities.