Interventions in occupational therapy use occupation (that is, any activity which is meaningful to an individual person) in order to achieve a particular therapeutic outcome. The same activity could be used by different therapists but in different ways to achieve different therapy goals. The same activity could be carried out by the SAME therapist with different clients in order to achieve different goals! To illustrate this point, consider gardening; an occupation which many people find meaningful.
The activity of planting seeds in a greenhouse. For one therapist, this could be creating repetitive upper limb and grasp movements in the low-tone limb of a stroke patient, to therapeutically restore neural connections for motor movement via neuroplasticity theory. For another therapist this could be teaching a learning disabled patient new skills in communicating with others and managing frustrations appropriately, in order to make successful socialising in the community and gaining employment more likely, via behavioural theory.
The same activity, but carried out with different end goals that the therapist wants the patients to achieve, and therefore different clinical reasoning behind it.
In this sense, it is not what you do, but why you do it.
Interventions can be grouped according to the type of goal they’re achieving: