People with mental health issues, substance use disorders, and/or developmental disabilities are often categorized as “low functioning” or “high functioning.” Which label they get depends on how well they can perform activities of daily living like cleaning their living space and cooking meals. Researcher and doctor Sidney Katz coined the concept of “activities of daily living” (ADL) in 1950, and it is still used today as part of Medicare criteria.
However, functionality labels do not capture everyone’s experiences. Just because a person struggles with certain activities does not mean they are incapable of doing well on other tasks or contributing to their communities. Likewise, someone with “high functioning” depression or substance use disorder can have severe symptoms that affect their quality of life.
Notice the difference between a line like “X works with a volunteer at a local nonprofit to prepare a monthly grocery budget” versus something more generic like “X, who’s low-functioning, has a hard time with basic tasks.” Specific, person-first language frames someone’s relative functionality as just one aspect of their identity that doesn’t define them.
At the sentence level, using phrasing that emphasizes a person’s agency — e.g., saying someone is “dealing with declining functionality” — reinforces that they are managing a situation that affects but doesn’t encompass all that they are. This level of nuance is especially important for conditions in which symptom severity vacillates over time.
Functioning refers to a person’s ability to engage in activities of daily living (ADL), such as maintaining personal hygiene, shopping for food, managing finances, and developing social relationships with other people. Using specifics and person-first language when describing functionality is a good way to frame challenges in these areas as just one aspect of someone’s identity that doesn’t define them.