Occupational therapy approaches rehabilitation through the concept of "occupation", the component of human behavior regarding one's engagement in self-initiated, self-directed, adaptive, purposeful, culturally relevant, organized activity. Rehabilitation through occupation is a process, stemming from interactions among the three domains: (a) performance areas; (b) performance components; and (c) performance contexts. At the core of the occupational therapy is a sub-process created by patients and therapists through their actions and reactions to treatment. It is a significant sub-process because it sets into motion the use of occupation as therapy. It is believed that the appropriate, therapeutic use of occupation affects "performance" or how one functions.

There is a need to develop ways to articulate and measure complex therapeutic interventions themselves. This is especially true of those treatment approaches which integrate human relationships, collaborative problem-solving, and the targeted doing of unique, personally relevant occupations. Occupational therapy is a health profession characterized by such interventions. The capacity to delineate key process variables may lead to credible examination of process-outcome relationships. Ultimately, results from the proposed study may provide information needed to further establish patient outcomes from occupational therapy interventions.