Biomedical Theory

BT assumes that patients are passive recipients of the doctors’ instructions. Health or disease can be traced back to causes of biomedical nature, such as viruses. Mechanic solutions such as pills are preferred instead of natural remedies. The reason for non-adherence is thought to be the patient characteristics, such as age and gender.

There is a major drawback to this approach because it ignores factors other than patient characteristics that may influence health behaviours, for instance, patients’ self-perceptions, social influences, and the impacts of the socio-economic environment.

Recent developments in biomedical theory have currently been incorporated into a biopsycho-socio-environmental theory, which incorporates a broader socio-environmental context into the analysis

Behavioural Learning Theory

A key objective of BLT is to develop adherence management skills and to protect the environment. An defining characteristic of BLT is its application of antecedents and consequences.

An antecedent can be internal (thoughts) or external (environmental impacts), whereas a consequence can be a punishment or a reward for a certain behavior. Criticism was leveled at BLT for downgrading an individual approach and not focusing on links outside to immediate rewards.

Communication Perspective

According to researchers who share the communication perspective, better doctor-patient communication will improve adherence. The foundation of this concept are patient education and healthcare worker communication.

Clarity is what usually lacks, while doctor-patient communication focuses on the timing of treatment, instruction and comprehension. Critics argue that the communication perspective ignores attitudinal, motivational, and interpersonal factors. Communication has been used in several adherence interventions, but rarely as the core component.

Cognitive Perspective

The cognitive perspective includes theories such as the health belief model (HBM), social-cognitive theory (SCT), theories of reasoned action (TRA), and planned behaviour (TPB), as well as the protection motivation theory (PMT).

Health-related behaviors are influenced by attitudes, beliefs, and expectations of future events and outcomes. People are likely to choose actions that will most likely result in positive outcomes when alternatives are available. There are several weaknesses to these theories, including non-voluntary factors that can affect behavior. There is no adequate emphasis placed on the skills needed to maintain adherence in these theories. Also, they do not pay much attention to the origins of beliefs and how these beliefs may influence other behaviors.

Information-Motivation-Behavioural Skills Theory

IMB focuses on three components that result in behavior change: information, motivation, and behavior skills. Having knowledge about a medical condition is an essential prerequisite for behavior change, but it is not sufficient by itself. In a favorable intervention, baseline information levels would be established, and gaps in information targeted.

The second component, motivation, is a function of adherence attitudes, perceived social support for the behavior, and a subjective model of how others with the same condition might behave. Moreover, behavioural skills include factors such as ensuring that the patient possesses the skills, tools, and strategies needed to perform the behavior as well as a sense of self-efficacy – the belief that they can succeed. To be effective, the components mentioned above must relate directly to the desired behavior. In addition, contextual factors such as living conditions and access to health care can moderate their impact. Behavioral skills are activated by information and motivation, which in turn lead to risk reduction behavioral change and maintenance. The theory has been shown to moderately affect behavior change and to predict adherence. The effects of this model were not assessed in any meta-analyses. With its simplicity and recent application to adherence, IMB is a promising model for promoting adherence. 

Health Belief Model

The HBM supports the view that a health behavior change must be based on a rational analysis of both the barriers to and the benefits of acting in such a way.

This perception of threat is influenced by cues to action, which can be internal (i.e., symptom perception) or external (e.g., health communication). The theory has recently been extended to include self-efficacy.

Protection Motivation Theory

In accordance with the PMT, one way to encourage behavior change is by appealing to a person’s fears. Researchers have identified three components of fear arousal: the magnitude of harm of a depicted event; the likelihood of that event occurring; and the effectiveness of the protective response.

The most recent version of the theory assumes that the motivation to protect oneself from danger is a positive linear function of beliefs that: the threat is severe, one is personally vulnerable, one can perform the coping response (self efficacy) and the coping response is effective (response efficacy). Among the major limitations of this theory is the fact that not all environmental and cognitive variables that might impact attitude change (such as the pressure to conform to social norms) are identified.

Self-Regulation Theory

People’s subjective experiences of threats are crucial to understanding how they adapt to health threats. As a result of past experiences, as SRT states, individuals form cognitive representations of health threats (and related emotional responses). Consequently, their responses to health threats are shaped by these representations, and the outcomes are impacted. According to the theory, people avoid and treat illness threats, and they are active, self-regulatory problem solvers. In defining coping strategies, it is implicitly assumed to lead to a state of equilibrium. The creation of health threat representations and coping strategies are based on individuals’ personalities, religious, social, and cultural contexts. There is a complex interaction between perceptions of the environment, symptoms, and beliefs about the causes. Meta-analyses examining evidence for the effectiveness of self-regulation theory were not found. Specific suggestions are needed to encourage adherence to these processes.

Social-Cognitive Theory

The theory is the most comprehensive one to date regarding behavior change. Based on social-cognitive theory, knowledge of health risks and benefits is a prerequisite for change, however additional self-influences are necessary for change to take place. Beliefs regarding personal efficacy are among some of these influences, and these play a central role in change. Behavior is also influenced by the expected outcomes – which could be the positive and negative effects of the behavior, as well as associated material losses or gains.

Outcomes may also be social, including social approval or disapproval of an action. A person’s positive and negative self-evaluations of their health behaviour and health status may also influence the outcome. Other determinants of behaviour are perceived facilitators and barriers. Behaviour change may be due to the reduction or elimination of barriers. In sum, this theory proposes that behaviours are enacted if people perceive that they have control over the outcome, that there are few external barriers and when individuals have confidence in their ability to execute the behaviour.

Theory of Reasoned Action

According to the TRA, most socially relevant behaviours are under the individual’s control, and the intention to perform a particular behaviour is both the immediate cause and the single best predictor of that behaviour. Attitudes towards an action affect intention to perform it.

Positive or negative beliefs and evaluations of the outcome of a behavior. Additionally, a person’s behaviour is influenced by subjective norms, including the expectations of others (e.g. family, colleagues) and the motivation of a person to obey others. Behavioural intention, it is contended, then results in action. The authors argue that other variables besides those described above can only influence behaviour if such variables influence attitudes or subjective norms. A meta-analysis examining this theory found that it could explain approximately 25% of variance in behaviour in intention alone, and slightly less than 50% of variance in intentions. 

This suggests that support for this theory is limited. Additionally, the TRA omits the fact that behaviour may not always be under volitional control and the impacts of past behaviour on current behaviours. Recognising this, the authors extended the theory to include behavioural control and termed this the TPB. An individual’s perception of the ease or difficulty of performing a particular behaviour is determined by their control beliefs.

Transtheoretical Model

According to TTM, people move through several qualitatively different, discrete stages and processes of change, relapse and revisit earlier stages before success. This theory provides an “integrative perspective on the structure of intentional change” – the perceived benefits and disadvantages of behaviours play a crucial role in behavior change.

There are independent variables that measure how people change their behavior and the covert and overt activities that help individuals become healthier. Each stage emphasises different processes.

Criticisms of TTM concern the stages postulated and their coverage and definitions, as well as descriptors of change. In their view, this theory violates all three of the basic assumptions of stage theories: qualitative transformation across discrete stages, invariant sequence of change, and non-reversibility. Moreover, the proposed stages might be only the different points of a larger continuum.

The above is based upon ‘A review of health behaviour theories: how useful are these for developing interventions to promote long-term medication adherence for TB and HIV/AIDS?’ by Salla Munro, Simon Lewin, Tanya Swart and Jimmy Volmink