Think of a public health or health care issue of importance to you. Explain this topic using either an inductive or deductive approach
EDITORIAL
The role of theory in evidence-based
health promotion practice
The recent emphasis on evidence-based practice
must be welcomed as part of the general move to
improve the quality and cost-effectiveness of health
promotion interventions. This Editorial aims to refocus attention on the role of theory in the context
of evidence-based practice. It argues that empirical
evidence alone is insufficient to direct practice,
and that recourse to the explanatory and predictive
capability of theory is essential to the design of
both programmes and evaluations.
The response to the current need for evidence
has been two-fold. On the one hand, we have
witnessed an increase in the number of published
systematic reviews [e.g. by the Cochrane Collaboration, NHS Centre for Reviews and Dissemination, and International Union for Health Promotion
and Education (IUPHE)], together with a call for
more robust evaluations from the field. On the
other hand, there has been considerable debate
about the nature of evidence and how we can
assess effectiveness. Concerns about the possible
dominance of a positivist methodological agenda
and its limited applicability to health promotion
have been more fully discussed elsewhere [see,
e.g. (Green and Tones, 1999)]. Signs are emerging
that these concerns are beginning to be addressed.
There is increasing recognition of the broad epistemological basis of health promotion research,
the value of methodological pluralism and the
particular capacity of qualitative methods to provide an illuminating perspective. Indeed the 51st
World Health Assembly urged all member states
‘to adopt an evidence-based approach to health
promotion policy and practice, using the full range
of quantitative and qualitative methodologies’
(WHO, 1998a). Furthermore, WHO recommendations to policymakers on health promotion evaluation (WHO, 1998b) also state strongly that ‘the
use of randomized control trials to evaluate health
promotion is, in most cases, inappropriate, misleading and unnecessarily expensive’ and advocate
the use of multiple methods.
© Oxford University Press 2000
The principal focus of much of the discussion
about evidence-based practice has been on the
appropriate measurement of effectiveness. The
role of theory has received comparatively little
attention in this debate. It is also noteworthy that
guidelines on undertaking systematic reviews
tend to side-step the issue. For many, theory is
equated with a reductionist position, and therefore
judged to be incompatible with both holism and
empowerment—the central tenets of health promotion. However, the accumulation of empirical evidence about effectiveness is of limited value to
the practitioner unless accompanied by general
principles which might inform wider application.
Without reference to these theoretical principles
we risk being submerged by a post-modern morass
of empirical evidence, which, on its own, can do
little to guide practice. Buchanan (Buchanan, 1994)
attributes scepticism about the value of theory and
the so-called theory practice gap to a restricted
view of theory shaped by the natural sciences and
positivism. He advocates a broader conceptualization of theory based on praxis—recognizing that
‘knowledge is contingent and contextual rather
than universal, determinate and invariable’. This
broader interpretation of theory is central to the
discussion here. The purpose of theory is seen not
as offering universal explanations or predictions,
but rather as enhancing understanding of complex
situations. Such understanding will inevitably need
to be sensitive to specific contextual factors, and
would necessarily draw on the experience of practitioners and communities.
Theory into practice
The US National Cancer Institute’s monograph
Theory at a Glance (National Cancer Institute,
1997) distinguishes two types of theory of relevance to the health promotion planning cycle—
explanatory theory and change theory. Explanatory
theory sheds light on the nature of the problem
and helps to identify the range of factors that the
health promoter might seek to modify. In contrast,
change theory informs the development and imple-
125
Editorial
mentation of intervention strategies. Without a full,
rational appraisal of the problem and possible
solutions, interventions might easily:
Address wrong or inappropriate variables (i.e.
miss the target completely).
d Tackle only a proportion of the combination of
variables required to have the desired effect
(i.e. hit only a few of the total number of
possible targets).
d
Theory also provides the basis for judging
whether all the necessary elements of a programme
are in place. For example, a programme designed
to encourage a particular behaviour, such as condom use, could not be expected to succeed unless
it addressed the known determinants of that behaviour. Providing young people with information
about condoms will have little effect unless they
also have the skills to obtain and use condoms,
they are able to be assertive in negotiating condom
use with their partner, condoms are available, and
so on. Theory can consequently make a major
contribution to improving the design of programmes and maximizing potential effects.
There are numerous theories to draw on. It
would be invidious to attempt to provide a comprehensive list. Theories range from behaviour theory
through change theory (at individual, organizational and community levels), to community development and policy theory. Reference has already
been made to the National Cancer Institute’s monograph. Nutbeam (Nutbeam, 1998) also provides a
succinct overview. Any difficulty arises not so
much from an insufficiency of theory, but rather
the capacity to select relevant theory and apply
it in practice. In an earlier Editorial, McLeroy
(McLeroy, 1993) was critical of the ‘theory a
week’ mode of teaching theory on health education
courses, leading to problems with using theory
constructively to tackle specific health issues. He
further contended that single theories cannot cope
with the complexity of ecological views of health
and that multiple theories might be required. However, there are no guidelines on the selection of
individual theories let alone combinations. It is
noteworthy, in this context, that relatively few
126
research and evaluation reports document fully the
theoretical analysis underpinning the development
of programmes and exactly how that analysis
was translated into action. Even fewer provide a
rationale for the selection of theoretical models.
Greater transparency about these issues in publications would be of immediate relevance to practitioners, and also contribute to a more general
understanding of the process of theory selection
and utilization.
Theory and evaluation
As we have noted above, reference to theory allows
an assessment to be made of whether all the
necessary elements of a programme are in place.
In the context of evaluation, this type of analysis
can be used to identify type III error, i.e. the
rejection of the effectiveness of a programme when
the programme itself was inadequate in terms of
design or delivery. Clearly, programmes developed
on an ad hoc basis—which we might refer to as
the ‘suck it and see approach’—are extremely
vulnerable to type III error.
It is somewhat surprising that systematic reviews
tend to pay scant regard to type III error. Inclusion
and exclusion criteria generally focus on the design
of the actual evaluation component of studies rather
than the quality of the intervention itself. The
principal concern is generally with establishing
criteria to ensure the avoidance of unjustified
claims for success, typically because there are
inadequate controls—usually referred to as type I
error. The quality of studies is therefore judged in
relation to the evaluation methodology, frequently
overlooking the adequacy of the programme itself.
Numerous authors have commented on the failure of a simple input–output model of evaluation
to address the complexity of the health promotion
endeavour. It is well recognized that evaluation
should be concerned with both process and outcome indicators. The key question revolves around
how these indicators are both identified and
selected. A thorough theoretical analysis can serve
to identify a whole range of potential outcomes as
a basis for making a selection of those judged
Editorial
to be most relevant. Furthermore, a theoretical
framework allows these indicators to be ordered
in relation to an anticipated time sequence—effectively constructing a proximal–distal chain of
events. Without such recourse to theory, the process
of selecting indicators can be rather like plucking
straws out of the air. Concerns that using theory
in this way might lead to a restricted, deterministic
view of events are unfounded provided an appropriate theoretical analysis is undertaken. Ideally
this should open up an array of possible indicators
and direct attention to those which are essential to
the needs of the evaluation—in essence sharpening
the focus of the evaluation. Moreover, distinguishing between proximal and distal indicators
allows some assessment to be made of the relative
magnitude of anticipated change—generally
greater in proximal indicators, such as change in
beliefs, than in more distal indicators, such as
change in behaviour. Inclusion of proximal indicators may therefore enhance the capacity of evaluation to demonstrate some effect and thus minimize
the risk of type II error—the failure to demonstrate
change which has actually occurred as a result of
the intervention. Such error generally arises when
the research design is insufficiently sensitive to
detect change or even focuses on inappropriate
variables. The use of theory to inform the design
of evaluation strategies is relevant to all types of
programme. It is worth emphasizing that recourse
to theory in identifying indicators need not be
restricted to those programmes that have a predetermined agenda. The argument applies equally
to interventions based on community development
principles, where the possible outcomes are more
open. In this instance relevant community development theory allows the various stages in the process
to be recognized and indictors appropriate to each
stage to be selected. Furthermore, theoretical
insight into processes such as group building,
project development, inter-sectoral collaboration
and organizational change can highlight appropriate process indicators.
It is perhaps important to re-iterate the point
that evaluation should be enhanced not restricted
by theoretical analyses. Clearly, openness to wider,
often unanticipated effects is also important in
evaluation design. Pawson and Tilley (Pawson and
Tilley, 1997) note that ‘realistic evaluation’ requires
understanding of contextual factors and the mechanisms by which interventions work in addition
to measuring outcomes. Such understanding is
particularly pertinent in the case of multifaceted
community interventions. The simple question
‘Does it work?’ needs to be supplemented by a
whole range of further questions to address the
full complexity of most intervention scenarios—
questions such as ‘How does it work?’, ‘What
components are necessary to success?’, What components are redundant?’, ‘Why does it work in this
context?’ (or equally importantly not work), ‘Can
it be replicated?’, ‘Is this an appropriate and
acceptable way of tackling the problem?’.
Building theory—an evolving cycle
We have argued above that the selection and use
of appropriate theory should be integral to the
design of health promotion programmes and evaluation strategies. The predictive capacity of theory
contributes to the quality of programmes by identifying the necessary elements for inclusion. Similarly this predictive capacity can serve to identify
a range of possible evaluation indicators (without
precluding unanticipated outcomes). The explanatory capability of theory allows generalizations to
be made and enhances understanding. However,
context-specific factors will also have some impact.
It is therefore essential to gain insight into the
conditions under which any observed relationship
holds true. As we noted earlier, considered
reflection on the outcome of programmes can serve
to corroborate theory or identify the need for
modification or refinement either in a general sense
or in relation to specific contextual factors. In
effect a continuous cycle of evolution is established
(see Figure 1) in which theory is used to direct
practice, but is also exposed to the scrutiny of
practitioners with regard to assessing its general
utility in the field and in a range of different
contexts.
Following on from recognition that evaluation
127
Editorial
Fig. 1. Theory, health promotion programme planning and evaluation.
Fig. 2. The development and application of theory—
hypothetico-deductive and inductive approaches combined.
strategies should not be restricted by positivist
perspectives, but should use both quantitative and
qualitative methods, the conceptualization of the
nature of theory and theory development should
be equally broad. We have already noted that
hypothetico-deductively driven approaches have
128
been criticized on the basis of being reductionist.
Their limited capacity to address all the concepts
and variables pertinent to complex situations may
be a source of some scepticism—particularly when
missing variables are immediately apparent to
experienced practitioners or communities. Inductively derived theory may serve to overcome these
shortcomings by providing explanatory insights,
which are firmly grounded in experience. Furthermore, it can define the conditions under which
theory holds true.
The move towards evidence-based practice has
triggered the publication of a series of systematic
reviews. What, then, is the place of systematic
reviews in this argument? The selection criteria
for studies to be included in systematic reviews
should recognize the importance of programme
design based on sound theoretical principles.
Reviews should not focus exclusively on outcome
measures of effectiveness, but also take account
of both the process and contextual factors. This
was recognized in the recent review of healthpromoting schools (Lister-Sharp et al., 1999),
which recommended that journal editors and peer
Editorial
reviewers should ‘ensure, in studies of school
health promotion interventions, that the following
are reported: the theoretical basis or assumptions
underpinning the interventions; the context of the
interventions; and the process of delivery’.
of theory in the light of empirical findings and
awareness of context-specific factors could contribute to a progressive narrowing of the theory practice gap. We may live in post-modern times, but
would be wise to take heed of Kurt Lewin’s dictum
that ‘there is nothing so practical as a good theory’.
Concluding remarks
It is undeniable that health promotion requires a
strong evidence base. However, if this derives
solely from the accumulation of empirical evidence
of effectiveness, there is a very real danger of
ending up with little more than a menu of proven
interventions from which to select and without a
rational base to guide that selection. Of more
relevance to the practitioner are general principles
together with an understanding of context-specific
factors, which will allow adaptation to suit different
situations.
The accumulation of empirical evidence per se
and development of theory need not be seen as
alternative and competing approaches. Rather, as
Wallace (Wallace, 1979) proposed a seamless web
incorporating hypothetico-deductive and inductive
elements into the scientific process, the two should
be inextricably linked as shown in Figure 2.
Theory needs to be developed and tested not
only in controlled situations, but also in the real
world where inductive insights can shape the
development of theory and its relevance in specific
contexts. However, in order for this to happen
studies need to document fully their theoretical
base and their rationale for the selection of theory.
Similarly, published accounts of how theory is
translated into practice together with refinement
Jackie Green
Senior Lecturer in Health Promotion
School of Health and Community Care
Leeds Metropolitan University
References
Buchanan, D. R. (1994) Reflections on the relationship between
theory and practice. Health Education Research, 9, 273–283.
Green, J. and Tones, K. (1999) Towards a secure evidence base
for health promotion. Journal of Public Health Medicine,
21, 133–139.
Lister-Sharp, D., Chapman, S., Stewart-Brown, S. and Sowden,
A. (1999) Health promoting schools and health promotion
in schools: two systematic reviews. Health Technology
Assessment, 3.
McLeroy, K. R., Steckler, A. B., Simons-Morton, R. M.,
Goodman, R. M., Gottlieb, N. and Burdine, J. N. (1993)
Social science in health education: time for a new model?
Health Education Research, 8, 305–312.
National Cancer Institute (1997) Theory at a Glance: A Guide
for Health Promotion Practice. http://rex.nci.nih.gov/
NCI_Pub_Interface/Theory_at_glance/HOME.html.
Nutbeam, D. and Harris, E. (1998) Theory in a Nutshell.
National Centre for Health Promotion, Sydney.
Pawson, R. and Tilley, N. (1997) Realistic Evaluation. Sage,
London.
Wallace W. (1979) An overview of elements in the scientific
process. In Bynner, J. and Stribley, K. (eds), Social Research:
Principles and Procedures. Longman, London, pp. 4–10.
WHO (1998a) Fifty-First World Health Assembly WHA51.12:
Health Promotion. WHO, Geneva.
WHO (1998b) Health Promotion Evaluation: Recommendations
to Policymakers. WHO, Copenhagen.
129
1
Inductive and Deductive Reasoning:
Evidence-Based Practices
Evidence-Based Public Health (MEDS 4053)
Kelley A. Carameli, DrPH
Week 5
2
Theory in Evidence-Based Practice
What is theory?
• Theory is a “general principle” that accounts for phenomenon
(particular cases or observations) by describing the underlying
processes of what is observed (or what is not observed).
• Theory approximates reality – it is our perception of the observed
(experienced) world using filters to distill and explain what we observe.
• Theory should be testable – use hypotheses and analysis to confirm/
reject the assigned meaning to our observations.
– This process of theory testing and building is called deductive (testing confirmation) and inductive (building – interpretation) reasoning.
• Theory is often missing from evidence-based analysis. Quantitative
statistical outputs (or qualitative text) lack intrinsic meaning…theory,
conclusion, or application provide the meaning or inference.
3
Theory in Evidence-Based Practice
Additional Qualities of ‘Theory’
• Theory assists in data interpretation and understanding.
– Data does not possess intrinsic meaning. Meaning must be inferred.
– Theory can explain health behavior – what informs it, changes it, and
how external influences affect it.
– Theory informs research design/strategy – what to measure and how,
what outcomes to expect.
• Theory is abstract, generalizable, and specific to the inquiry.
– Explanatory – what informs behavior? E.g., knowledge, attitudes,
efficacy, social support, resources (Health Belief Model)
– Change – what actions should be taken? E.g., used in program
evaluation, intervention development (Stages of Change Theory)
4
Theory in Evidence-Based Practice
Connecting Theory to the Scientific Method
• Theory informs our research design, metrics, analyses, and results.
• Theory is how we seek meaning in (explain) what we observe (data).
Theory
Research
Design
Concepts /
Measures
Analyses
Interpretation
/ Conclusions
Application
• Analysis is the intersection of theory and observation (data).
– Analyses test predictions and observations for hypothesized relationships.
– Analyses modify theory (inductive); theory informs analyses (deductive).
• Why test X to predict Y? If X and Y correlate – does the relationship have
purposeful meaning? We often stop at the “number” without asking “why”.
5
Theory in Evidence-Based Practice
Linking Theory and Analysis
1. Individual / Intrapersonal Models
– What we know and think (cognitions) affects how we act (behaviors).
– Knowledge is necessary, but not sufficient, to produce change. Other
influential factors: skills, motivation, social norms, environment.
Theory
Constructs and Model
Variables for Analysis
(Abstract)
(Abstract)
(Defined / Operationalized)
Stages of Change
Pre-contemplation → Contemplation →
Decision → Action → Maintenance
Contemplation: Readiness
to eat healthy on Oct. 19.
(DiClemente, Prochaska)
Health Belief Model
(Rosentstock)
Theory of Planned
Behavior (Ajzen)
Perceived: Severity,
Susceptibility,
Benefits, Barriers,
Self-Efficacy
→ Perceived Threat
↓
[Behavior]
↑ Cues to Action
Attitudes & Intentions
→
Social & Subjective Norms
Perceived Power & Control
Intentions
↓
[Behavior]
Self-Efficacy: Likelihood to
engage in vigorous exercise
20-min. a day.
Subjective Norms: My peers
support me eating healthy
with moderate exercise.
6
Theory in Evidence-Based Practice
Linking Theory and Analysis
2. Interpersonal Models
– People are influenced by, and in turn influence, their environments.
Theory
Constructs and Model
Variables for Analysis
(Abstract)
(Abstract)
(Defined / Operationalized)
Social Cognitive
Theory
Person: knowledge, attitudes
Environment: social norms, observations
Behavior: skills, efficacy
Reinforcement: Maintaining a
healthy diet and weight results
in lower insurance costs.
(Bandura)
•
•
•
•
•
•
Environmental
Social Norms / Reinforc.
Observational Learning
Reciprocal Determinism
Cognitive / Person
Knowledge
Expectations
Attitudes
Health Behavior
•
•
•
Behavior
Skills / Capability
Practice
Self-Efficacy
7
Theory in Evidence-Based Practice
Linking Theory and Analysis
3. Community Models
– How systems function and change. Behavior as a social process.
Theory
Constructs and Model
Variables for Analysis
(Abstract)
(Abstract)
(Defined / Operationalized)
Diffusion of
Innovations
Innovation: relative advantage, compatibility,
complexity, trialability, observability
Communication: P1 ↔ P2 and P1 → P2
Time: innovators, early adopters, early majority,
late majority, laggards
Social System: change agents, opinion leaders
Compatibility: There is time in
my daily schedule / routine to
exercise for 20-min.
(Rogers)
8
Theory in Evidence-Based Practice
Linking Theory and Analysis
Theory gives us meaning / direction. Analysis connects theory and observation.
• Theory is a collection of ideas. Analysis is a set of tools.
• We cannot directly observe the abstract (constructs, relationships, pops.),
but can observe what is measurable (variables, associations, samples).
• Both are needed in scientific inquiry.
– Theory informs (→) what we seek to observe…deductive
– Observations inform (→) how to assign meaning…inductive
ABSTRACT
Interpretation /
Inferred
Theory
Data Analysis
Measured
↔
Constructs
Variables
Relationships ↔ Associations
↔
Populations
Samples
CONCRETE
Testing /
Known
Observation/Data
Qualitative and/or
Quantitative
9
Inductive and Deductive Reasoning
Inductive and Deductive Logic and Research
• In logic and theory there are often two broad methods of reasoning:
– Deductive: reasoning from the general to the particular (observed)
– Inductive: reasoning from the particular to the general (theory)
Deduction
Theory → Observation
Theory
(General Principle)
Observation/Data
(Particular Examples)
Induction
Observation → Theory
10
Inductive and Deductive Reasoning
Directionality of Logical Reasoning
Deductive
Inductive
Reasoning from the general to
the particular
Reasoning from the particular
to the general
Theory
Observation / Data
Hypothesis
Tentative Hypothesis
Observation/Data
Pattern
Confirmation
Theory
11
Inductive and Deductive Reasoning
Brief Reminders
• Logical reasoning (or scientific inquiry) often starts with an exploratory
inquiry (Type I evidence) that something must be done.
– Descriptive inquiry provides information on the prevalence, incidence,
or affected populations with the health issue.
– Explanatory inquiry provides information on the associations (or
inferred relationships) between behavior and health issue.
• In all cases, ‘theory’ is usually an underlying factor.
– Biology: ‘theory’ of virus and antibody mechanisms (for vaccines)
– Physics: ‘theory’ of gravitational pull between forces or objects
– Economics: ‘theory’ of incentives and free markets.
• Theories are tested and refined, but rarely fully ‘proved’.
• Even ‘observed’ qualities of analysis can lack objectivity.
12
Making Connections
Connecting It All together
• Deductive: Data gathered to support or dispute a hypothesis, then
generalized to the larger population (hypothesis → data)
• Inductive: Data gathered before a hypothesis is formed (data → hypothesis)
Deduction: Theory → Observation/Data
ABSTRACT
Interpretation /
Inferred
Theory
Data Analysis
Measured
↔
Constructs
Variables
Relationships ↔ Associations
↔
Populations
Samples
CONCRETE
Testing / Known
Observation/Data
Induction: Theory ← Observation/Data
Qualitative and/or
Quantitative
13
Application: Deductive / Inductive
Tobacco Use
Deductive
Inductive
1. Theory (General Principle):
Smoking is hazardous to one’s
health.
1. Observation (Particular Case):
Smoking tobacco is on the rise. So is
lung cancer and other serious
illnesses.
2. Observation (Particular Case):
Smoking is a principal cause of
lung cancer and other serious
illnesses, and second hand
smoke kills 35,000 people a year.
Type I evidence: smoking, lung
cancer association; incidence.
3. Deduction:
Smoking should be banned in
public spaces.
2. Induction / Inference:
Smoking tobacco can kill you (i.e., lung
cancer and other serious illnesses).
3. Theory (General Principle):
Tobacco smoking is hazardous
to one’s health.
Yes, but is this the only inference from the observation?
Maybe stress or environmental determinants also impact
death OR tobacco use AND are also on the rise.
14
Application: What Can We Learn?
Apply Inductive Reasoning…what do you observe
across these ads regarding tobacco? What are the
patterns you see? What might be your theoretical
conclusion?
15
Application
Apply Deductive
Reasoning…our
reasoning tells us that
tobacco is harmful…
what do you observe
across these ads about
tobacco? Is your
reasoning confirmed?
Theories and Models Frequently Used in Health Promotion
As you are planning or describing your program, referring to individual, interpersonal, or
community-level theories that relate to health behavior change is sometimes useful. For
example, these theories might be used in the “Causal Assumptions/ Theory of Change” column
in your logic model or to help you identify potential points of intervention.
Theory/Model
Summary
Key Concepts
For people to adopt recommended physical
activity behaviors, their perceived threat of
disease (and its severity) and benefits of
action must outweigh their perceived
barriers to action.
Perceived susceptibility
Perceived severity
Perceived benefits of
action
Perceived barriers to
action
Cues to action
Self-efficacy
Stages of change
(transtheoretical
model)
In adopting healthy behaviors (e.g., regular
physical activity) or eliminating unhealthy
ones (e.g., watching television), people
progress through five levels related to their
readiness to change—pre-contemplation,
contemplation, preparation, action, and
maintenance. At each stage, different
intervention strategies will help people
progress to the next stage.
Pre-contemplation
Contemplation
Preparation
Action
Maintenance
Relapse prevention
Persons who are beginning regular physical
activity programs might be aided by
interventions that help them anticipate
barriers or factors that can contribute to
relapse.
Skills training
Cognitive reframing
Lifestyle rebalancing
Information processing
paradigm
The impact of persuasive communication,
which can be part of a social marketing
campaign to increase physical activity, is
mediated by three phases of message
processing—attention to the message,
comprehension of the content, and
acceptance of the content.
Exposure; Attention
Liking/interest;
Comprehension; Skill
acquisition; Yielding
Memory storage
Information search and
Retrieval; Decision;
Behavior; Reinforcement;
Post-behavior
consolidation.
Individual
Health belief model
Theory/Model
Interpersonal Level
Social learning/ social
cognitive theory
Theories and Models Frequently Used in Health Promotion
Summary
Key Concepts
Health behavioral change is the result of
reciprocal relationships among the
environment, personal factors, and
attributes of the behavior itself. Self-efficacy
is one of the most important characteristics
that determine behavioral change.
Self-efficacy
Reciprocal determinism
Behavioral capability
Outcome expectations
Observational learning
Theory of
reasoned action
For behaviors that are within a person’s
control, behavioral intentions predict actual
behavior. Intentions are determined by two
factors—attitude toward the behavior and
beliefs regarding others people’s support of
the behavior.
Attitude toward the
behavior
• Outcome expectations
• Value of outcome
expectations
Subjective norms
• Beliefs of others
• Desire to comply with
others
Theory of planned
behavior
People’s perceived control over the
opportunities, resources, and skills needed
to perform a behavior affect behavioral
intentions, as do the two factors in the
theory of reasoned action.
Attitude toward the
behavior
• Outcome expectations
• Value of outcome
expectations
Subjective norms
• Beliefs of others
• Desire to comply with
others
Perceived behavioral
control
Social Support
Often incorporated into health promotion
interventions, social support can be
instrumental, informational, emotional, or
appraising (providing feedback and
reinforcement of new behavior)
Instrumental support
Informational support
Emotional support
Appraisal support
Individual Level
Theory/Model
Theories and Models Frequently Used in Health Promotion
Summary
Key Concepts
Community Level
Community
organization model
Public health workers help communities
identify health and social problems, and
they plan and implement strategies to
address these problems. Active community
participation is essential.
Social planning
Locality development
Social action
Ecological approaches
Effective interventions must influence
multiple levels because health is shaped by
many environmental subsystems, including
family, community, workplace, beliefs and
traditions, economics, and the physical and
social environments.
Multiple levels of
influence
• Intrapersonal
• Interpersonal
• Institutional
• Community
• Public policy
Organizational change
theory
Certain processes and strategies might
increase the chances that healthy policies
and programs will be adopted and
maintained in formal organizations.
Definition of problem
(awareness stage)
Initiation of action
(adoption stage)
Implementation of change
Institutionalization of
change
Diffusion of innovations
theory
People, organizations, or societies adopt
new ideas, products, or behaviors at
different rates, and the rate of adoption is
affected by some predictable factors.
Relative advantage
Compatibility
Complexity
Trialability
Observability
Sources:
1.
2.
3.
Alcalay R, Bell RA. Promoting Nutrition and Physical Activity Through Social Marketing: Current Practices and
Recommendations. Davis, CA: Center for Advanced Studies in Nutrition and Social Marketing, University of
California, Davis; 2000.
National Institutes of Health. Theory at a Glance: A Guide for Health Promotion Practice. Bethesda, MD:
National Institutes of Health, National Cancer Institute; 1995.
US Department of Health and Human Services. Physical Activity and Health: A Report of the Surgeon General.
Atlanta, GA: US Department of Health and Human Services, Centers for Disease Control and Prevention,
National Center for Chronic Disease Prevention and Health Promotion.
This table adapted from:
US Department of Health and Human Services. Physical Activity Evaluation Handbook. Atlanta, GA: US Department
of Health and Human Services, Centers for Disease Control and Prevention; 2002, Appendix 3, pg. 43.
(http://www.cdc.gov/nccdphp/dnpa/physical/handbook/pdf/handbook.pdf)
Health and Human Sciences
HHS-792-W
Models and Theories to Support
Health Behavior Intervention
and Program Planning
Vicki Simpson PhD, RN, CHES, Purdue School of Nursing
Developing health promotion programs that support
healthy lifestyle behaviors requires comprehensive
planning. Program planners can use models and
theories to guide this process as they work with
individuals, groups, and communities. Individuals
and communities have multiple risky lifestyle
behaviors including physical inactivity, unhealthy
diets, smoking, and stress. Also, there are often
many factors that can affect an individual’s or
community’s ability to effectively change behaviors,
including low income, lack of access to safe places
to exercise, inaccessibility of healthy food, and
cultural and ethnic differences.
These factors can make determining how to best
design a program seem like an overwhelming task.
To be effective, programs must not only address
the behavior, but also the factors that surround it.
Models and theories can provide a framework for
program planners to build upon as they develop
health promotion programming.
This publication discusses three models or
theories related to health behavior change that can
help planners design effective health promotion
programs: socioecological, transtheoretical, and
health belief. Before describing these models,
it is useful to first understand some basic terms,
including theory, model, concept, and construct.
Basic Concepts
Merriam-Webster defines a theory as “an idea or set
of ideas that is intended to explain facts or events.”
Models refer to a more descriptive process. In other
words, a model may describe how a process occurs
but not necessarily why it occurs in that way.
Theories and models both include concepts and
constructs. Concepts are the primary components
of a model or theory. Constructs are components
that have been created for use in a specific model
or theory. These terms are important to understand
when discussing models and theories (Glanz, Rimer,
& Lewis, 2002).
Health behavior models and theories help to explain
why individuals and communities behave the way
they do. Planners can use these models and theories
to increase the effectiveness of their program
design, implementation, and evaluation. It’s
useful to remember that different models may be
appropriate in different situations. There is no onesize-fits-all approach; each individual or community
requires programming that is tailored specifically to
their needs.
Tailoring that programming may require planners
to consider multiple models or theories when they
develop programs and interventions to support
lifestyle behavior changes. A mix of approaches
helps to provide the best support and guidance to
individuals, groups and communities as they work
to develop healthy lifestyle behaviors (Glanz,
Rimer, & Lewis, 2002).
organized social institutions. These institutions
have formal or informal policies and structures.
Socioecological Model
The first model, the socioecological model,
addresses behavior change at multiple levels and
considers the inter-relationship between behavior
and the environment. The model accounts for
multiple factors that can influence the behavior
change process.
4. Community factors — these describe
the relationships among organizations and
institutions. This includes community norms.
5. Public policies — these refer to policies or
regulations concerning healthy practices.
The model identifies five levels of influence on
health behavior and discusses the reciprocal
relationship between them (Stokols, 1996;
McLeroy, Bibeau, Steckler, & Glanz, 1988):
In the socioecological model, an individual’s
behavior influences and is influenced by factors in
the other levels (Glanz, Rimer, & Lewis, 2002).
Using this model allows a program planner to
consider factors from multiple levels that can
impact health.
1. Intrapersonal factors — these include
individual characteristics such as knowledge,
beliefs, and self-concept. Most health promotion
programming is aimed at this level.
For example, to develop programming for adult
obesity, a planner must first understand the
policies, structures, behaviors, and norms that
support obesity in the community. Communities
that do not have access to healthy food or
low-cost exercise options will have difficulty
supporting an individual who attempts to become
healthier. While individual lifestyle factors are
important to consider, this model encourages
the planner to identify interventions to influence
factors where individuals live, work, and play. See
Figure 1.
2. Interpersonal processes and primary
groups — these include the individual’s social
environment such as family, friends, peers,
and co-workers that surround the individual
and influence behavior. In turn, an individual’s
behavior also influences family, friends, and
peers (National Cancer Institute [NCI], 2005).
3. Institutional or organizational factors —
these refer to workplaces, churches, and other
Intrapersonal
Factors
• Educate communities about
strategies to decrease obesity
• Encourage counseling to
increase self-confidence
Interpersonal
• Encourage individuals
to exercise with peers
• Offer community
walking groups
Institutional
Community
• Encourage workplaces to • Develop social media
provide environments that campaigns with health
messages
support health with fitness • Work with communities
facilities, healthy food
to provide healthy
options
food options
Public
• Advocate for legislation
that supports healthy
policies
• Apply for funding to
address obesity
Figure 1. A socioecological approach to obesity. This figure shows interventions that program planners can take at each level of the
socioecological model to implement a health program that targets obesity.
2
It is important to be aware that this process can
be cyclical. Individuals may start at one stage
and progress forward, or may go backward. The
model includes several other important concepts
that help describe factors or activities that occur
as individuals attempt to make a behavior change.
These include weighing the benefits and costs
of making a change, evaluating the impact of
the change, finding support for the change, and
determining whether or not they can confidently
make the change to a healthy behavior (Glanz,
Rimer, & Lewis, 2002; NCI, 2005).
Transtheoretical Model (Stages of Change)
The transtheoretical model describes the process of
behavior change and accounts for an individual’s
readiness to make and sustain behavior changes.
This model is useful because it helps planners
design programs based on an individual’s readiness,
motivation, and ability.
The model includes five stages (Glanz, Rimer, &
Lewis, 2002; NCI, 2005):
1. Precontemplation — in this stage, the
individual has no intention to change behavior
within the next six months. The individual may
lack knowledge or may have been unsuccessful
with previous attempts at a change.
While there are some similarities to the
socioecological model, this model focuses on
helping the individual to move through the stages
toward a sustained behavior change.
2. Contemplation — in this stage, an individual is
considering a behavior change within the next
six months. Ambivalence, however, may keep
the individual from progressing to the next stage.
For example, if a program planner uses the
transtheoretical model to address obesity, then the
planner must determine the individual’s current
stage of change in relation to lifestyle behaviors
that lead to obesity. In most cases, several
behaviors contribute to obesity. Figure 2 shows
interventions using this model to address physical
inactivity as a contributor to obesity. These
interventions are tailored specifically to each stage
with the hope that the individual will respond by
moving forward in the behavior change process
described by this model.
3. Preparation — in this stage, the individual takes
some steps toward making a change and doing
so within the next 30 days.
4. Action — an individual reaches this stage once
he or she has made an apparent behavior change
for six months or less.
5. Maintenance — if the individual’s behavior
change lasts for more than six months, he or she
moves into the final stage, maintenance.
Maintenance
• Encourage individuals to
expand their physical
• Help the individual identify activity options and to
Preparation
strategies to maintain
• Support any increases in
support others who may
Contemplation
physical activity. Help find physical activity, address
be considering a behavior
• Help the individual identify potential resources to
barriers, and set goals.
change.
Precontemplation barriers to physical
Support confidence to
support exercise, such as
• Educate the individual about activity and encourage
maintain the change.
peer support systems,
obesity and the role exercise them to develop exercise
reminder cues, rewards.
plans.
plays, including pros and
cons of the change.
Action
Figure 2. A transtheoretical model approach to physical inactivity. This figure shows interventions that program planners can implement at each
stage to support an individual’s behavior change related to physical activity.
3
that spur individuals toward action. For example an
individual may see a television ad featuring a wellknown actor discussing weight-loss strategies.
Health Belief Model
The health belief model is one of the oldest models
of health behavior, but is still very relevant when
discussing health behavior change. This model
addresses the readiness to act upon a health
behavior based upon several individual beliefs.
These beliefs include:
Self-efficacy refers to an individual’s confidence
that he or she can successfully carry out the
indicated actions. If individuals do not believe they
can successfully make a behavior change, they are
unlikely to do so (Rimer, Glanz, & Lewis, 2002;
NCI, 2005).
1. Perceived susceptibility — refers to beliefs
concerning risk or susceptibility to a condition or
disease.
This model can be very useful in designing health
promotion programming. For example, most
individuals are very aware that obesity often leads
to the development of diabetes. Figure 3 shows how
planners can use the health belief model to develop
interventions to address obesity to avoid diabetes.
In this example, the interventions are aimed at
educating individuals to increase their perceived
susceptibility to and seriousness of diabetes as an
outcome of obesity.
2. Perceived severity — refers to beliefs concerning
the possible severity of a disease or condition.
3. Perceived benefits — refers to the perceived
value or benefit of behavior changes in reducing
the risk of a condition or disease.
4. Perceived barriers — refers to any obstacles or
barriers to the behavior changes being considered
to decrease risk.
Education also helps individuals discover the
benefits of decreasing their risk of diabetes by
losing weight. Helping individuals to identify
and eliminate barriers may help them see that the
benefits outweigh the barriers, thus encouraging
actions to avoid the development of diabetes by
dealing with their obesity.
If individuals perceive they are susceptible to a
condition (1) and that the condition could be severe
(2), they will most likely take action to avoid the
condition. The likelihood of action is enhanced if
the perceived benefits (3) outweigh the perceived
barriers (4).
The model also includes two other constructs: cues
to action and self-efficacy. Cues to action are events
• Educate individuals
concerning obesity as a
risk factor for diabetes.
Perceived
Susceptibility
Perceived
Severity
Perceived
Benefits
Perceived
Barriers
• Educate individuals about the
benefits of increased physical
activity and healthy diets in
reducing the potential risk for diabetes.
• Discuss the potential effects
of diabetes management
or complications on the
individual’s quality of life.
• Encourage individuals to
discuss potential barriers such
as lack of access to exercise
facilities, healthy foods, etc.
Figure 3. A health belief model approach to addressing obesity as a factor in diabetes. This figure shows interventions that program planners can
use to help individuals change their behaviors to avoid the risk of diabetes.
4
Summary
Each model reflects different, yet related,
dimensions of the behavior change process.
Determining which model to use will depend upon
the situation. In many cases, planners may find that
using more than one model is appropriate or that
only certain aspects of a model are useful.
References
Glanz, K., B. Rimer, , & F. Lewis. (2002). Health
behavior and health education. San Francisco,
CA: John Wiley & Sons, Inc.
National Cancer Institute (2005). Theory at a glance
guide for health promotion practice.
McLeroy, K. R., D. Bibeau, A. Steckler, & K.
Glanz. (1988). An ecological perspective on
health promotion programs. Health Education &
Behavior, 15(4), 351-377.
Consider a program planner who is working with an
obese individual whose family members seem to be
able to eat whatever they want without developing
diabetes. In such instances, the health belief model
may be useful. In this example, the planner may
need to enhance the interventions for perceived
susceptibility.
Stokols, D. (1996). Translating social ecological
theory into guidelines for community health
promotion. American Journal of Health
Promotion, 10(4), 282-298.
If an educator is working with a group of
low-income individuals who are dealing with
obesity and work for the same employer, the
socioecological model may be more useful. The
planner may need to aim more effort to create
and support healthy work environments and find
resources that provide low-income individuals
opportunities for exercise and healthy food options.
Theory [Def. 1.]. (n.d.). Merriam Webster Online.
In Merriam Webster online. Retrieved October
26, 2014, from www.merriam-webster.com/
dictionary/theory.
In both of these examples, the transtheoretical
model may help an educator determine what
interventions are appropriate to move both groups
along the continuum toward behavior change.
Models and theories can help us understand
behavior and plan health promotion programming.
They also can remind us to consider and address
the many variables and factors that affect the
behavior change process at the individual, group,
and community levels. The three models discussed
in this publication are among the most commonly
used. However, there are many more models and
theories that explain. The availability of multiple
models and theories allows the program planner
to support design of effective health promotion
programs.
Mar 2015
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