“Now that you understand middle range theory, look through the list of middle range theories in your text. Find 2-3 that are related to concepts that you are interested in and read about them. Can you determine what type of theory it is? What are the concepts? How could this theory be used for research or practice?

Theory is made up of concepts and propositions about a phenomenon.
Concept = word or phrase that captures the essence of something such as functional status or mood.
For example: a single dimension might be physical energy. On the other hand, a multidimensional might be functional status which would include several factors.
A proposition is a statement about one or more concepts. For example, Functional status is defined as performance of usual activities of daily living. A proposition about two or more concepts states an association between the concepts, including the relation between the concepts or the effect of one or the other. So, nursing theory focuses on experiences of health conditions and health related events.
Types of middle range theory

Descriptive: describe a phenomenon. Typically comprise one concept and one proposition that is a definition or description of the concept.

Examples include “Theory of Functional Status”. The concept is functional status. The proposition is that it is a multidimensional concept that is defined as performance of usual family care activities, household activities, social activities, community activities, person care activities and of occupational activities.

Explanatory: Specify how concepts are related to one another, they provide explanations about a phenomenon. They consist of two or more concepts, the propositions that are definitions or descriptions of each concept, and the propositions that specify the relations between the concepts.

Example: The theory proposition that specifies the relation between concepts is as follows: chronic pain, physical disability, social support, age, and gender are related to perceived daily stress, which is related to depression.

Predictive: Specifies how a concept affects one or more other concepts. They are made up of two or more concepts the propositions that are definitions or descriptions of each concept, and the propositions that specify the effect(s) of one concept on one more other concept.

Example: A theory about the effects of cancer support groups with coaching on symptom distress, emotional distress, functional status and quality of the relationship with a significant other. Women with breast cancer who participate in a cancer support group with coaching would have less symptom distress, less emotional distress, greater functional status, and higher quality of relationship with a significant other than women who participated in a cancer support group without coaching and women who did not participate in any support group.