What is the term for the decreased ability of a person to perform a task independent of context or environment?

The term that reflects a decreased ability of a person to perform a task independent of context or environment is functional limitation. This concept emphasizes the individual's capacity to complete tasks or activities due to some form of impairment that may hinder their performance. Functional limitations can arise from various factors such as injury, illness, or disability, which ultimately impact how a person engages with their daily activities regardless of where they are or the specific circumstances of their environment.

In contrast, functional ability refers to the overall ability to perform tasks and live independently, emphasizing what a person can do rather than what they cannot. Task performance is more about the individual's technique and effectiveness in completing specific tasks, while activity restriction focuses on the constraints imposed on someone’s ability to participate in certain activities due to external factors rather than personal capacity alone. Hence, functional limitation best captures the essence of the decreased ability in question.