Theories of behaviour change

Behavior change models and theories attempt to explain why behaviors change. These theories cite personal, behavioral, and environmental, characteristics as the major factors that determine behavior. There is no single behavior change theory because behavior itself has multiple determinants. Each behavioral change theory or model focuses on different factors as they try to explain and predict what changes behavior the best? Research has also been conducted regarding specific elements of these theories, especially elements like self-efficacy (explained below) that are common to several of the theories. There is increased interest in the application of these behavior theories not only in the area of health but also in the fields of education, criminology, energy and international development with the hope that understanding behavioral change will improve the services offered in these areas.


Some of the commonly used models / theories of behavior change are described below. These models can be classified into two broad types:

(i) Individual-level behavior change models, and

(ii) Health promotion models for changes at larger level (especially Social-ecological model)


While the individual-level models focus on the individual determinants of change, on risk behaviors and protective behaviors, the health promotion models also focus on social, economic, organizational, cultural and larger environmental influences on health and illness. In a previous unit or session we discussed the “bio-psychosocial” approach to disease and illness and it is important to keep that in mind when reading the larger social-ecological models of behavior change.



The individual-level behavior change models can be classified into two broad types

(a) Stage models

(b) Social-cognition models


Stage models of individual-level behavior change classify people according to discrete stages (example, the Trans-Theoretical Model below); and that people can move between these discrete stages to achieve the desired behavior. The health professional can usually tailor the intervention to the specific stage of change.


Social-cognition models of behavior change such as the health Belief Model described below are based on the assumption that an individual evaluates the costs and benefits of a particular health-related action. Thus, health actions or health behaviors are based on decisions made by this individual further to that cost-benefit analysis. If the health professional can understand and address those determinant factors that influence this cost-benefit decision-making, then perhaps the health professional can sway or persuade that individual to adopt the desired behavior. The factors that impact on the decision are usually the attitude, norms, self-efficacy, perceived risks among others. Thus, if the health professional can communicate to client and address these factors then there is a greater likelihood of the desired health action / behavior occurring.



In 1983 James Prochaska & Carlo DiClemente developed a Transtheoretical model (TTM)which has been used as the basis for developing many effective interventions to promote health behavior change. The “Trans-theoretical Model” is an integrative model of behavior change and grew from systematic integration of more than 300 theories of psychotherapy, along with analysis of the leading theories of behavior change.


The aspect that makes the TTM unique is the idea that change occurs over time, an aspect generally ignored by many other theories of change. This time dimension of the theory proposes that a person may progress through five stages of change when trying to modify his / her behavior.


Unlike traditional theories of behaviour change, the TTM makes no assumption that all individuals are ready for an immediate and permanent behavior change. It recognizes that different individuals will be in different stages. The model also emphasizes designing interventions according to the needs of the individuals at different stages thereby encouraging retention in the process towards final behavior change and maintenance of this change.


These five stages of change of TTM are:

(1) The first stage of the TTM is the pre-contemplation stage, where people have no intentions of taking action in the foreseeable future, usually measured as the next six months. Individuals in this stage may be un-informed or under-informed about the consequences of their behavior.The main trait of someone in the pre-contemplation stage is they show resistance to recognizing or modifying a problem behavior. For an individual to move out of this stage they must experience cognitive dissonance, a negative affective state, and acknowledge the problem.

(2) In the next stage, contemplation, although the individuals still engages in the risk behavior, he / she is intending on making a change within the next six months. He / she isweighing the pros and cons of making the change. This weighing process can cause them to remain here for long periods of time. An individual will move on to the next stage if he or she perceives that the pros outweigh the cons and if the force of motivation is stronger for change than it is for remaining stable.

(3) By the time individuals enter the Preparation stage, the pros in favor of attempting to change a problem behavior outweigh the cons, and action is intended in the near future, typically measured as within the next thirty days.An individual in this stage may not know how to proceed to make a change and could be nervous about his or her ability to change. Individuals will move to the next stage when they select a plan of action that they feel will work and if they feel confident that they can follow through with the plan.

(4) In the Action stage, individuals have made efforts to modify their behaviors, experiences, or environments within the last six months to overcome their problem.Research warns us not to mistake this visible action of trying to change with the change itself. The individual’s actual change only occurs when a certain criteria has been reached, a criteria which scientists and professionals agree is sufficient to reduce risks to health created by the problem behavior. For instance, a person may be taking IFA tablets regularly but that does not mean the problem of anemia has been solved.

(5) The final stage of the TTM is Maintenance wherein people work to prevent relapse and secure their gains made during action. The ability to remain free from the problem-behavior and the ability to participate in new incompatible behaviors for more than six months is the criteria used to categorize someone into the maintenance stage.


The stages of change are often measured using questions that ask about current behavior, future intentions, and sometimes past attempts to change. As the individual moves through the 5 stages of changethere are various processes/activities/strategies that help him/her move through these stages. At each stage the individual also needs ‘decisional balance’ and ‘self-efficacy’ to enable him/her to move to the next stage.


Decisional balance refers to the individual’s weighing of the pros with the cons, the benefits of changing the behavior, and the costs of changing the behavior.


Self-efficacy is “the situation-specific confidence people have that they can cope with high-risk situations without relapsing to their unhealthy or high risk-habit.” A change in the level of self-efficacy can predict a lasting change in behavior if there are adequate incentives and skills. Studies have shown that temptation (of falling back into the risk behavior) and self-efficacy have an inverse relationship with one another across stages of change, which suggests that temptation is highest during the earlier stages of change and lowest during the later stages.



While the stages of change describe the actual shift from one stage to another, the processes of change describe how these shifts occur. Some of the processes that providers can use to help clients / patients progress through the stagesof change are described briefly below:

Consciousness Raising—increase awareness of the client through the provision of information, education, and personal feedback about the healthy behavior
Self-Reevaluation—helping client realize that the healthy behavior is an important part of who they are and want to be
Environmental Reevaluation—helping client realize how their unhealthy behavior affects others around them (especially their loved ones) and how they could have more positive effects on their loved ones by changing
Self-Liberation—helping client believe in her or his ability to change and making commitments to act on that belief
Helping Relationships—help client to find people who are supportive of the desired change
Reinforcement Management—help client to actively increase the rewards that come from positive behavior and reducing those that come from the negative behavior
Stimulus Control— Use reminders and cues that encourage healthy behavior
The TTM is generalizable across a broad range of problem behaviors as well as a wide variety of populations with such behaviors. Studies have also examined the TTM over a range of populations including different work-site groups such as medical, industrial, retail, and governmental, as well as age groups, places of residence such as rural and urban, medical conditions, and countries.



The Health Belief Model (HBM) relates largely to the cognitive factors that predispose a person towards adopting or rejecting particular health behavior. HBM assumes that behavior is determined by a number of beliefs about threats to an individual’s well-being and the effectiveness of particular actions or behaviors. Some constructions of the model feature the concept of self-efficacy alongside these beliefs about actions. These beliefs are further supplemented by additional stimuli referred to as ‘cues to action’ which trigger actual adoption of behavior.


Perceived threat is at the core of the HBM and is linked to a person’s ‘readiness’ to take action. It consists of two sets of beliefs about an individual’s perceived susceptibility or vulnerability to a particular threat and the seriousness of the expected consequences that may result from it. The effectivenessof a behavior in reducing the threat (perceived benefits) are weighed against the perceived costs and negative consequences ofadopting the behavior (perceived barriers) such as the side effects of treatment. By weighing these pros and cons, theperson establishes the overall extent to which a behavior is beneficial to himself / herself.


The health belief model (HBM)was developed by researchers at the U.S. Public Health Service in the 1950s during a study of why people sought X-ray examinations for tuberculosis; soon afterwards it was applied extensively to immunization. HBM has often been applied to the behavior of clients seeking various health services. There are some conditions (also see diagram), according to HBM, that both explain and predict a health-related behavior:

The individual client believes that his or her health is in trouble OR has a belief in susceptibility to a disease or health problem
o for the behavior of seeking a screening test or examination for an asymptomatic disease such as tuberculosis, hypertension, or early cancer, the person must believe that he or she can have the disease and yet not experience any symptoms. This set of beliefs was later referred to generally as “belief in susceptibility.”


The individual perceives the “potential seriousness” of the condition
o in terms of pain or discomfort, time lost from work, economic difficulties, or other outcomes.

The individual believes that benefits from adopting the recommended behavior outweigh the costs and inconvenience
o In the health belief model, these are “perceived” or “anticipated” benefits and costs.

The individual believes that these behaviors / actions are indeed possible and within his or her grasp. Self-efficacy is a judgment of one’s ability to perform the desired behavior. The individual’s perceived capacity to adopt the behavior (self-efficacy) is a key component of the model.
The person receives a “cue to action” or a precipitating stimulus that makes the person feel the need to take action.The HBM identifies two types of ‘cues to action’; internal, which in the health context includes symptoms of ill health, and external, which includes media campaigns or the receipt of other information and communication from health providers. These cues affect the perception of threat and can trigger or maintain behaviour. This cue to action could come from a health professional who talks directly to the client or conducts community events.

The model leaves much to be explained by factors enabling and reinforcing one’s behavior, and these factors become increasingly important when the model is used to explain and predict more complex lifestyle behaviors that needs to be maintained over a lifetime.

The health belief model was one of the most frequently applied model in published descriptions of programs and studies in health education and health behavior in the 1990s. It has since been displaced in frequency of application by the transtheoretical model (TTM) of stages of change. It remains a valuable guide to practitioners in planning the communication component of health education programs.



The social ecological model of health promotion and health behavior states that health is mediated by factors at various levels of the ecosystem such as the individual level, interpersonal level, community, organizational, social and supranational or global level (See Figure below). The social-ecological perspective finds that factors at various levels of the eco-system work to influence an individual’s circumstances and behavior. This type of analysis examines a problem on the individual, interpersonal, community, and societal levels, and holds that interventions directed at all of these levels will have a synergistic effect.Paying attention to and analyzing each of these levels is essential for understanding the multi-layered dimensions of health and health issues.

The socio ecological approach to health promotion practice emphasizes the complex interaction between individual behavior and environmental determinants. It recognizes that individuals are nested within families, communities, organizations, societies and the global context, and that these varied levels of existence shape health. The socioecological approach encourages practitioners to integrate systemwide interventions with personfocused efforts to modify behavior and/or the environment in which the individual lives.

Because of its emphasis on complexity and systemwide intervention, the socioecological approach has been regarded as challenging to operationalize. Thus, despite the emergence of the socio-ecological approach as an ideal model for health promotion programming, it has not been widely integrated into practice. Most behavior change efforts have typically focused on individual behaviors rather than broader levels of influence.

One reason for this discrepancy between the ideal and practice in health promotion is the inherent complexity of the socio-ecological approach, which requires consideration of multiple levels of determinants of a problem, as well as relationships between the levels. Using a comprehensive approach in planning and implementing interventions is a daunting process. Most health providers getdiscouraged because they feel they cannot do anything about communities and social norms. However, when the entire public health center works like a team along with the stakeholders (see previous units) then it is possible to address these multiple levels and achieve greater change than what one can achieve simply at the individual level.

However, classifying the problem itself at various levels (such as individual, interpersonal, community, and societal) can help to identify appropriate targets for intervention.The nature and origins of various causes of maternal and child (MCH) morbidity and mortality can be explained using a socioecological model.

Example of Socio-ecological Analysis of the Current MCH Intervention Approaches: How does each of these levels contribute to a health phenomenon or to mortality and morbidity?

The Malnutrition-Infectioncycle is a major problem in many children in India.Factors such as poor access to nutritious food, overcrowded living conditions and poor hygiene and sanitation contribute to this problem. Children who live in conditions of poverty, lack food security, and their parents are poorly educated about health. These children are systemically disempowered and at an increased risk of malnutrition and many other health and human development problems.

Compounding the interpersonal nature of disease determinants, are the organizational forces at play. Poorly organized and underresourced health care systems often fail to deliver timely and effective treatment. Furthermore, despite the existence of food distribution systems, the quality of quantity of food served through centers and schemes and mid-day meals are often poor. Problematically, the emergence of antibiotic resistant strains poses an added challenge for already overstretched health systems. Policies are passed but these policies are never properly implemented due to systemic issues in implementation.

Inadequate community resources and pollution often characterize poor community environments, and affect individual, interpersonal and organizational determinants of disease. Furthermore, the poor communities lack the proper sanitation and WASH (water, sanitation and hand-washing) habits. A lack of capacity coupled with scarce resources has implications for society’s ability to improve health at other socioecological levels in the context of malnutrition-infectious disease.

Thus, as discussed abovechildhood malnutrition and gastrointestinal infections / infestations are determined by a number of socioecological factors.

The social-ecological modelrecognizes that there are multiple determinants of any health condition, especially something as complex as maternal and child health. Mothers and children are embedded within networks, communities and systems. The barriers to healthy behaviors may often lie outside of the individual in the family, interpersonal network, community, societal culture or even within the health care institution. Therefore, in addition to counselling or communicating with the individual mother / pregnant woman, it is also critical to address the multiple determinants of disease that lie at different levels of the social-ecological system in which the mother and child live such as the family, community and society.

However, many health professionals throw up their hands because even though the broad framework of the socio-ecological model is useful for analysis. After all what can an individual health professional do to address larger complex social determinants? Through further training in communication methods, the health professional can be trained to conduct community mobilization and public advocacy. By learning these approaches of mobilization and advocacy, the health professional can then not only play a role inside the clinic but also work with various players and stakeholders at the community and system level to bring about the desired increase in healthy behaviors.