Theory You Can Use
This section provides an introduction to the main theories behind the work that we do.
What is theory and how can it help?
A theory presents a systematic way of understanding events or situations. It is a set of concepts, definitions, and propositions that explain or predict these events
or situations by illustrating the relationships between variables. Theories must be applicable to a broad variety of situations. They are, by nature, abstract, and
don't have a specified content or topic area. Like empty coffee cups, theories have shapes and boundaries, but nothing inside. They become useful when filled with
practical topics, goals, and problems.
Concepts are the building blocks (the primary elements)of a theory.
Constructs are concepts developed or adopted for use in a particular theory. The key concepts of a given theory are its constructs.
Variables are the operational forms of constructs. They define the way a construct is to be measured in a specific situation. Match variables to constructs when identifying what needs to be assessed during evaluation of a theory-driven program.
Models may draw on a number of theories to help understand a particular problem in a certain setting or context. They are not always as specified as theory.
Health behavior and health promotion theories draw upon various disciplines, such as psychology, sociology, anthropology, consumer behavior, communication and
marketing. Theory allows us to move beyond intuition to design and evaluate interventions based on understanding of behavior. It helps us to step back and consider the
larger picture. Using theory as a foundation for program planning and development is consistent with the current emphasis on evidence-based interventions in public
health, behavioral medicine, and medicine.
Theory provides a road map for studying problems, developing appropriate interventions, and evaluating their successes. Theory can also help to explain the dynamics of
health behaviors, including processes for changing them, and the influences of the many forces that affect health behaviors, including social and physical environments.
Theory can also help planners identify the most suitable target audiences, methods for fostering change, and outcomes for evaluation.
Theory guides the search for reasons why people do or do not engage in certain health behaviors; it helps pinpoint what planners need to know before they develop public
health programs; and it suggests how to devise program strategies that reach target audiences and have an impact. Theory also helps to identify which indicators should
be monitored and measured during program evaluation. For these reasons, theory-based program planning, implementation, and monitoring are more likely to succeed than
those developed without a theoretical perspective.
No single theory dominates health education and promotion, nor should it; the problems, behaviors, populations, cultures, and contexts of public health practice are
broad and varied. Some theories focus on individuals, while others examine change within families, institutions, communities, or cultures. Adequately addressing an
issue may require more than one theory, and no one theory is suitable for all cases.
Because the social context in which behavior occurs is always evolving, theories that were important a generation ago may be of limited use today. At the same time,
new social science research allows theorists to refine, adapt or even unite existing theories. As a result, some constructs, such as self-efficacy, are central to
multiple theories.
Effective practice depends on using theories and strategies that are appropriate to a situation.
How do you choose an appropriate theory?
Choosing a theory that will bring a useful perspective to the problem at hand does not begin with a theory (e.g., the most familiar theory, the theory mentioned in a
recent journal article, etc.). Instead, this process starts with a thorough assessment of the situation: the units of analysis or change, the topic, and the type of
behavior to be addressed. Because different theoretical frameworks are appropriate and practical for different situations, selecting a theory that "fits" should be a
careful, deliberate process. Start with the following guide.
Characteristics of a Useful Theory.
A useful theory makes assumptions about a behavior, health problem, target population, or environment that are:
Logical;
Consistent with everyday observations;
Similar to those used in previous successful programs;
Supported by past research in the same area or related ideas.
SOURCE: National Cancer Institute. (2005). Theory at a Glance: A Guide for Health Promotion Practice. 2nd ed.
