1. HBHE600-881 Psychosocial Factors in Health-Related Behavior
Theories and Conceptual Models
Sara J. McLaughlin, PhD, MPH
Department of Health Behavior and Health Education
University of Michigan School of Public Health

2. Today’s Agenda Definition and characteristics of a…
theory
conceptual model
Role of theories and conceptual models in health interventions
Different types of variables commonly included in conceptual models

3. Definition of a Theory
“…An attempt to explain what we see in the empirical world around us.” (p. 125)
Source: Taylor, V. A., & Bengtson, V. L. (2001). Sociological perspectives on productive aging. In N. Morrow-Howell, J. Hinterlong & M. W. Sherraden (Eds.), Productive Aging: Concepts and Challenges (pp ). Baltimore, MD: The John Hopkins University Press.

4. A theory tells us …
What causes or explains the occurrence of some class of phenomena
How the various factors thought to cause or explain the phenomena are related to one another
Source: van Ryn, M., & Heaney, C.A. (1992). What’s the use of theory. Health Education Quarterly, 19(3),

5. Theory of Reasoned Action
BEHAVIORAL
BELIEFS
EVALUATION
OF BEHAVIORAL
OUTCOMES
INTENTION TO PERFORM BEHAVIOR
BEHAVIOR
ATTITUDE
TOWARD
NORMATIVE
MOTIVATION
TO COMPLY
SUBJECTIVE
NORM

6. A few characteristics of a theory…
Generalizable: Instead of being situation or context specific, a theory is applicable to a wide range of situations and contexts
Testable: Must be able to test whether the specified relationships are actually true or not; can measure the various components
Abstract: Typically not specified in great detail or focused on one particular phenomenon
Sources: van Ryn, M., & Heaney, C.A. (1992). What’s the use of theory. Health Education Quarterly, 19 (3), ; Glanz et al., Chapter 2

7. Theory of Reasoned Action
BEHAVIORAL
BELIEFS
EVALUATION
OF BEHAVIORAL
OUTCOMES
INTENTION TO PERFORM BEHAVIOR
BEHAVIOR
ATTITUDE
TOWARD
NORMATIVE
MOTIVATION
TO COMPLY
SUBJECTIVE
NORM

8. Constructs and Variables: Definitions
Constructs: The core components of a specific theory
Variables: The operational form of constructs; in other words, how the construct is measured
Source: Glanz et al., Chapter 2

9. Theory of Reasoned Action
BEHAVIORAL
BELIEFS
EVALUATION
OF BEHAVIORAL
OUTCOMES
INTENTION TO PERFORM BEHAVIOR
BEHAVIOR
ATTITUDE
TOWARD
NORMATIVE
MOTIVATION
TO COMPLY
SUBJECTIVE
NORM

10. Theories can…
Help you understand why people may or may not be engaging in optimal health behaviors
Highlight things you should consider when developing interventions to promote healthier behaviors
Can provide focus
Sources: Earp and Ennett,1991; Glanz et al., Chapter 2

11. A conceptual model is…
“a diagram of proposed causal linkages among a set of concepts believed to be related to a particular public health problem.”
Source: Earp and Ennett, 1991, p.164

12. The Fathers and Sons Intervention Program Model.
Caldwell C H et al. Health Educ. Res. 2004;19:
Health Education Research Vol.19 no.6, © Oxford University Press 2004; All rights reserved

13. Theories vs. Conceptual Models
Theories are general; a single behavioral theory encompasses a wide range of behaviors, populations, and settings
Conceptual models are specific; they focus on a particular behavior in a distinct population and setting
Sources: Earp and Ennett, 1991; Glanz et al., Chapter 2

14. Conceptual models…
Help us organize our thinking about the causes of a particular problem or the factors that influence a behavior
Summarize and integrate what we know about a particular phenomenon
Relationships among the factors believed to influence a behavior or health problem are clearly specified
Can help us design more effective interventions and research studies
Sources: Earp and Ennett, 1991

15. Steps in Developing a Conceptual Model
Step I. Outcome Identification
Step II. Identification of Factors that Influence the Outcome
Existing research; personal knowledge and experience; theories
Step III. Specify the Relationships (i.e., draw arrows) among Identified Factors
Existing research; existing conceptual models; theories; Personal knowledge and experience
Sources: Earp and Ennett, 1991

16. Steps in Developing a Conceptual Model
Step IV. Review Model and Begin Narrowing the Focus
Cannot address every aspect of a problem
What is most important?
What can you realistically expect to accomplish?
Model is limited to those aspects of the problem that are addressed in your study or intervention
Model development is not easy. Will involve several (if not many) attempts before you arrive at your “final” model.
Sources: Earp and Ennett, 1991

17. Six Types of Variables in Conceptual Models…
Outcome or Dependent Variable: The factor that is the focus of your study or intervention
Predictor or Independent Variable: A factor that causes or influences the outcome of interest

18. Example A
Predictor
Outcome
Physician
Advice
Exercise

19. Six Types of Variables in Conceptual Models…
3. Antecedent Variable: A factor that precedes the predictor/independent variable of interest

20. Example B

21. Six Types of Variables in Conceptual Models…
4. Mediating Variable: A variable that comes between the predictor and outcome
A mediating variable is caused by the predictor and at least partially explains how the predictor causes the outcome

22. Example C Stress Obesity Predictor Outcome Stress Dietary Intake
Mediator

23. Six Types of Variables in Conceptual Models…
Modifying Variable: A factor that changes or “modifies” the relationship between the predictor and outcome

24. Example D Antecedent Physician Training Predictor Outcome Physician
Advice
Exercise
Exercise
Knowledge
Modifier

25. Six Types of Variables in Conceptual Models…
6. Confounding Variable – A variable that is related to both the predictor and outcome variable that when not accounted for may result in a misleading association between a predictor and outcome

26. Example E Predictor Smoking Outcome Safe Sex Practices
Alcohol Consumption
Predictor
Smoking
Outcome
Safe Sex
Practices
Confounding
Variable

27. See you next time…