Grand theory presenters start theoretical formulation at abstraction level and these formulations never link the realities. Roy’s (1971) work was designated for the grand theory. Roy presented the adaptation model. In the adaption model of Roy, a person was perceived as receiving the adaptive system for inputs. This input may be as the stimuli from the external environment, which is processed by the feedback or internal processes. These processes are inherent in the changing abilities of individuals and result into an output in the form of either ineffective response or adaptive (Parse, 2001).
Middle range Theory is less abstract and more specific in its scope, which reflects a practice and also addresses the specific phenomenon. This theory deals with a limited number of aspects of real world concepts. A mid-range theory is made up of relative concrete concepts, which are concrete propositions and defined operationally. These concepts can be tested empirically.
A period of ten years ago, Georgene Eakes, Mary Burke, and Margaret Hainsworth developed the theory of Chronic Sorrow. This is the application of the middle range theory of nursing that explains the periodic recurrence of a continuous sadness or grief feeling over an important loss. This presents the normal response to the loss. Because, parents always felt sadness over their children’s mental retardation and this response was not permanent. Clinicians could intervene in these conditions if they had similar beliefs. This theory also related with the feelings of parents who have premature infants. Hainsworth, Eakes, & Burke (1994) found that mothers of those children with the spina bifida also had a pervasive sadness.
This theory focuses upon the specific phenomenon, which mirror out the clinical practices and has narrowest interest range.