Elements of Theory

Concept - building blocks of theory; it classify the phenomena of interest.
         1. Theoretical Concepts:
                   Abstract concepts - are mentally constructed, independent of a specific time or place.
                               Example: transport; cardiovascular disease
                   Concrete Concepts - are directly experienced and related to a particular time or place.
                               Example: wheelchair; myocardial infarction
         2. Operational Concept:
                   Discrete concepts - identifies categories or classes of phenomena, such as patient, nurse, health                                                  or environment.
                               Example: Marital Status; Patients
                   Continuous concepts - permits classification of dimension or gradation of a phenomenon on a                                                      continuum.
                               Example: number of children; degree of temperature

St    Statement - in a theory, may state definitions or relations among concepts; are the chains that link the blocks (concepts) to build a theory; propose relationships between the properties of two or more concepts or variables.

When a statement is relating two or more concepts or variables we can identify the independent from the dependent variable.

Ø Independent – cause, can be manipulated; antecedent or determined

Ø Dependent – effect, can be measured; consequent or resultant

Example: 

If a scientist conducts an experiment to test the theory that a vitamin could extend a person’s life-expectancy, then:

• The independent variable is the amount of vitamin that is given to the subjects within the experiment. This is controlled by the experimenting scientist. 
• The dependent variable, or the variable being affected by the independent variable, s the life span.

Types of Statement:

1. Theoretical Statement - relate concepts to one another; permits analysis

2. Operational Statement - relate concepts to measurements.

Theory - are set of interrelated concepts that give a systematic view of a phenomenon that is explanatory and predictive in nature.

Theory construction:

    1. Deductive - reasoning is narrow and goes from general to specific.

Example: All men are mortal;

              Socrates is a man

              Therefore, Socrates is mortal

  2. Inductive - reasoning is much broader and explanatory un nature as one goes from specific to general.

  3. Abductive - reasoning begins with an incomplete set of observations and proceeds to the likeliest possible explanation for the set.