This study aims to operationally define a relatively small, but growing field of study on the development, application, and evaluation of practical implementation models for health behavior change in the context of international development. The paper examines the continuum of behavioral theories and their application in the context of development programs and research in low- and middle-income countries (LMICs). We describe practical implementation models, point out that they have many strengths in terms of feasibility and evaluability for a range of issues, and examine how they have been used to design theory-based interventions for development.
First, we review the concept of a continuum from theory design and testing to implementation models in development programs. At the theory design end of the continuum, behavior change is conceptualized as highly complex, and this is a barrier to implementation, evaluation, and building a robust evidence base in international development programs due to the need for relative simplicity in programs implemented in low-resource contexts (1). Here, we argue that for implementation practice to be successful, models need to be relatively simple and easy to implement, and we identify examples of such models. This paper defines and systematically reviews the literature on such implementation models.
Continuum of behavioral theory
Behavioral and social science theories or models are often multi-dimensional and complex. They typically use a set of predictors, constructs, and explanations to systematically understand what motivates behavior and, in the context of public health, how to design effective interventions using this information to change and improve health behaviors at the population level (1). However, behavioral theories generally do not focus on resource constraints that can complicate carrying out health-promoting behaviors at the individual level. These are the types of constraints that are typically present in international development programs in LMICs, and in programs serving low-income populations in high-income countries (HICs).
Health and resource inequalities in turn make use of social and behavioral theories difficult to sustain and heavily dependent on the ability to influence knowledge and attitudes over time. Since not all groups possess the opportunity (i.e., situational conditions), ability (i.e., task knowledge) and motivation (i.e., attitudes, beliefs, norms) (OAM) to modify behaviors (2), some research offers a conceptual framework for guiding and regulating public health behaviors through tools available in education, marketing and law (3). This framework views OAM as the key variables in behavioral choice. It posits that perceptions of self-interest and trade-offs present in the marketplace of choices constrain what interventions can do to maximize societal-level health and well-being (3).
There is a growing body of evidence that theory-based interventions are more successful in health behavior change programs compared to interventions lacking theoretical underpinnings (4,5). The literature on health behavior theories has given rise to wide-ranging interventions that aim to catalyze behavioral change constructs to advance health-supporting policy and programming, in areas such as health communication for Zika prevention (6), improved child health (7), and nutrition/dietetic practices (8). Prominent frameworks include the health belief model, transtheoretical model, social cognitive theory, and social-ecological model (4), all of which involve multi-dimensional constructs such as perceived vulnerability, social norms, self-efficacy, response efficacy, decisional balancing, and context-specific circumstances that mediate behaviors and, therefore, can promote or hinder desired behavioral change (9). The literature is expansive on the use of such theories in behavioral medicine (10), as well as targeting specific behaviors, such as tobacco use, alcohol misuse and unhealthy diets, family planning, sexual risk taking, and others that contribute to widespread morbidity and mortality (11,12,13).
Theory and program implementation
The use of theories for health promotion and efforts to change unhealthy behaviors is rooted in an understanding that health and social development problems do not exist in isolation. They are a function of interacting factors – sociocultural, economic and geographic – at different levels, for example, individual, family and community (including institutional factors), that impact personal agency and individual choices and decisions (4). Therefore, health behaviors are critically intersectional in that they cannot be understood based on one factor but rather multiple factors that merge in diverse ways in connection with micro and macro environments, race, ethnicity, gender, biology, and socioeconomic status. This is especially true with regard to access to health resources and inequalities, as exemplified by the COVID-19 pandemic (14).
The complexity of intersecting factors facing behavior change interventions makes it critically important that theory be relatively simple and easy to apply. Practitioners, especially in international development, need theories that are pragmatic and can be applied despite resource constraints and other implementation barriers that may be present in LMICs. Implementation models, as we describe them in this paper, attempt to demystify theory and isolate essential variables such as OAM that can be addressed in a development context.
The foregoing discussion emphasizes that context is important to implementation science, in particular developing tailored program approaches and identifying and promoting evidence-based practices (15). Current literature suggests that translating research findings to public health practice is challenging because diffusion through communication channels and social systems (16) does not always adequately consider the settings or populations in which the intervention is introduced or applied (17). In some instances, ineffective planning and intervention and evaluation strategies, and weak or non-existent testing also make it challenging to integrate evidence-based interventions into policy and practice (18). Notwithstanding these issues, just as diffusion processes aim to move research to translation, dissemination, and practice paradigms, there also is a process of diffusion from behavioral theory development and research to implementation and intervention development in varied contexts (19). At the level of theory development and research to establish evidence that supports theory, this is important and desirable for practice-based fields such as public health.
A primary use of behavioral theories is to design health interventions that will advance positive outcomes and expand evidence-based programs through diffusion, dissemination and implementation activities (20). However, in the context of implementation, particularly within development programs, theoretical complexity becomes a barrier to successful practice and program execution, adaptation, and evaluation (21,22). As such, practical implementation models have a number of strengths in terms of feasibility and evaluability for a range of issues. Given the diffusion process inherent to health behavior interventions and public health, and emphasis on implementation and scaling, the literature shows that implementation models exist. Moreover, there is an actionable core set of principles that such models adopt, including underlying constructs of opportunity and motivation, to understand behavior and encourage behavior change.
Implementation model examples
One example is the Fogg Behavioral Model (FBM) that posits the three core elements of motivation, ability and a prompt, or trigger, “must converge at the same moment for a behavior to occur” (23). Fogg, the creator of the FBM, also identified a range of behaviors that can be modified depending on the prompt and temporal aims of whether the behavioral change is a single event, desired over a specific period, or to be taken up indefinitely (24). The typology organizes behaviors by goal or action gradients of whether the target behavior is new, familiar, or an existing behavior that is sought to be increased, decreased or completely stopped (24). Although relatively new to public health applications, the FBM has been used to assess the impact of a social marketing campaign on condom use (25). The model also has prompted research on whether interventions should aim to increase motivation or ability in the uptake of health-promoting behaviors, as in the case of exploring social norms influences on modern contraception use among Nigerian women (26).
Another framework for understanding human behavior and guiding interventions is the “COM-B system.” Michie and her colleagues developed this framework in which the “COM” refers to components of capability, opportunity, and motivation that “interact to generate behaviour that in turn influences these components” (15). As such, one or more of the core elements can be targeted in a behavioral change intervention. The researchers also created a “behavioral change wheel” to aid in characterizing and designing interventions, assuming relevant policies and resources exist in context to enable an intervention (15). For instance, using the wheel as a guidepost, multiple operations within the intervention, such as incentives, restrictions, and education, can be used to address the core components for a desired behavioral outcome. The COM-B mnemonic has been used to analyze barriers and facilitators for behaviors in connection with chlamydia testing (27) and postnatal lifestyle choices following diagnoses of gestational diabetes (28), as well as intervention design for hearing aid use (29). There has been substantial use of COM-B by some international institutions, such as the World Health Organization (WHO) (30). This study investigates the extent to which models such as COM-B have appeared in the peer-reviewed literature on behavior change in LMICs.
A third example is the EAST framework developed by the quasi-governmental Behavioural Insights Team based the in United Kingdom (31). Taking cues from behavioral economics and psychology, “EAST” forms a mnemonic that refers to easy, attractive, social and timely as key principles to understand and encourage behavior. Finding that “policymakers and practitioners find it useful to have a simple, memorable framework to think about effective behavioural approaches” (31), the developers were inspired to simplify the longer list of Messenger, Incentives, Norms, Defaults, Salience, Priming, Affect, Commitments, and Ego (MINDSPACE) influences on behaviors (15,31). The UK government has suggested local officials encourage restaurants to use the EAST model to spur healthy eating behaviors (32). It also has been used to address violence in humanitarian settings (33) and develop interventions to promote walking (34) and improve mental health (35).
One common characteristic of these models is their attention not only to individual characteristics (e.g., attitudes, beliefs, and other personal factors), but also to the intersecting environmental factors that influence behavior. In the OAM framework described earlier, implementation models address not only motivation (e.g., my beliefs about a behavior and intention to act), but also opportunities and ability to act in the environmental context.
The aim of the present study is to operationally define implementation models, examine how they have been applied in international development, and conduct a systematic review of the published literature in this area in accord with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. To the best of our knowledge, there are no studies that have examined the literature for implementation models or attempted to define such models with a core set of inputs.
The main research question (RQ1) is the following: What is the extent and nature of evidence published in this field? Two additional hypotheses are:
(H1) There are examples, such as the Fogg Behavioral Model and others, that have established evidence for practical implementation models; and
(H2) There are some practical implementation models that represent best practices and may be recommended as a basis for resources and intervention design in the context of international development. The study will describe the state of evidence for feasible implementation models for development and promote the growth of future efforts and evaluation research in this area.