A systematic review of adaptations of evidence-based public health interventions globally

Emphasis on evidence-based practice in medicine, public health, and the social services has led to a prominence of the application of practice guidelines and evidence-based interventions or EBIs. When situating an EBI in a new context, public health professionals, or health practitioners who work in community settings, sometimes adapt the EBI during the process of replication [1, 2]. However, in planning and implementing these interventions, there may be mismatches between the original EBI and the characteristics of the population of interest, implementing agency, and/or community [3]. In addition, agencies may lack the resources, funding, or expertise to deliver the EBI as it was originally intended [4]. Consequently, public health professionals often make both intended and unplanned program adaptations to the EBI to better fit the new audience or context.

The concept of program adaptation was originally introduced by Rogers when he defined adaptation as the degree to which an innovation is modified in the process of its adoption and implementation [5]. Other definitions have evolved in the era of translation of EBIs and the emergence of adaptation frameworks (Table 1). These definitions share similar characteristics, including modifying a program to meet the needs of the target population, local circumstances, or new contexts. Some definitions focus on the need to retain the core components or logic of the program [6‐11]. The adaptations could be deletions, additions, or modifications [11]. Some posit that adaptations should be systematic or planned [12‐14] to involve stakeholder input and to have a more rigorous process in program planning, while the CSAP (Center for Substance Abuse Prevention) framework notes that adaptations could be accidental modifications [11]. Moore and colleagues proposed the schema of timing of adaptation of proactive (planned) vs. reactive [15]. Furthermore, three definitions included modifications related to matching the culture for the new population, “cultural adaptation” [11, 16, 17]. A few definitions specify elements that could be changed such as program components, content, provider, and delivery [11, 14]. Of these definitions, CSAP’s Guidelines for Adaptation [11], Map of Adaptation Process [16, 18], ADAPT-ITT [9], and Research-based Program Adaptation [6] are cited most frequently in the published literature. In summary, although many adaptation definitions share similar characteristics, the most frequently cited ones do not emphasize the same concepts. Thus, it is important to discern how professionals in the field describe their adaptations, why they make modifications and the types of changes that they make, and how they use frameworks to conduct adaptations.

Previous reviews have found that modifications to original EBIs often occur spontaneously when they are adopted into other practice settings [1, 15]. Common reasons for adaptations include responding to participants’ attributes [18, 19], needs [20] or culture [15], constraints such as limited time or resources [15, 19‐21], issues related to participant recruitment or retention [15], and accommodating practice or setting circumstances/context [20].

Increased development of models and frameworks to guide the adaptation of EBIs began with national EBI dissemination efforts related to disease prevention areas in substance abuse and HIV/AIDS [6, 9, 14] or cultural adaptations to existing programs [7, 22]; these frameworks provide approaches to facilitate adaptation. Escoffery and associates recently conducted a scoping study that found 13 adaptation frameworks [23]. They reported 11 common steps including assess the community, understand the intervention, select intervention, consult with experts, consult with stakeholders, decide what needs adaptation, adapt the original program, train staff, test the adapted materials, implement, and evaluate. These frameworks enhance the translation of evidence-based practices. As Wandersman’s Interactive Systems Framework suggests, supports are necessary to guide the public health system or agencies to adopt and implement new public health interventions [24]. These frameworks assist public health professionals as capacity building tools for a structured adaptation process.

Limited research has explored how adaptation occurs in practice. Little is understood about who is involved in adaptation processes, what common types of changes are made to the original program, and what mechanisms are used. This review advances the concept of adaptation and elucidates common adaptation processes in real-world community settings as reported in the published literature. Community settings are defined as various organizations or places in communities such as schools, faith-based organizations, social services or public health agencies, households, or worksites. The research questions for the review were as follows:

We followed procedures for systematic reviews based on the Cochrane Handbook of Systematic Reviews of Public Health Interventions [25] and the reporting guideline, Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) [26].

We found 543 unique citations that yielded 45 articles reporting 42 distinct program adaptations after the two levels of screening (Fig. 1). Main reasons for exclusion were a lack of description of the adaptation process or methods, not being a public health program or policy, and not being a primary study (e.g., protocol, review).

This study presents findings based on a systematic review of published reports of adaptations of 42 EBIs. We present a systematic characterization of reasons for adapting EBIs, types of modifications made, steps taken during adaptation, reference to existing adaptation frameworks, and the constructs measured in evaluations of the adapted EBIs. In our review, the most common reasons for adaptation were to be relevant to a particular culture or new population, and to implement a program in a new setting. A previous study by Moore also found cultural adaptation to be a common reason for adaptations among evidence-based grantees, although less frequently (43% compared to our 64%) [15]. Higher frequency reasons in Moore’s study were related to resource constraints or logistics: lack of time (80%), limited resources (72%), difficulty retaining participants (71%), and resistance from implementers (64%) [15].

Among our included reports, all adaptation teams, or individuals involved in the research or adaptation, conducted content modifications, most commonly tailoring, adding or removing elements, and shortening. In their review of 32 published descriptions of interventions implemented in routine care or community settings, Stirman and colleagues also found the same four content modifications most frequently reported [1]. Consistent with the Stirman review, we found that context modifications were the next most frequently mentioned type of adaptation for either the program population or setting. Stirman, however, also found that format changes were frequently described [1]. In our review, delivery modifications were described in the majority of the studies, with training and evaluation modifications much less common. It is unclear whether these did not occur or were less often reported. Moore’s review found slightly different frequencies of modifications, with more reports of changes related to logistics such as changes in delivery and dose, and much less frequent content changes [15].

Like Krivitsky, we also found that 29% reported removing elements [34]. This type of adaptation should be explored more because of its implications for reducing the fidelity to program core elements and potentially reducing the EBI’s effects [35]. Additionally, four studies explicitly described changing the core elements of the original EBI. This is an area of concern because the integrity of the original program could have been jeopardized. More research is needed to understand why the elements were deleted and if the program implementers (i.e., researchers, community planners) consulted others before undertaking this change. The low reporting of changes to core elements may be because it is difficult to identify what the core elements are in an EBI. They may include elements that are readily adapted such as delivery or content. However, unless the original developers of the program or health-related online clearinghouses or resources where they are housed clearly describe them, it is often difficult for planners to identify them. Therefore, considerations of fidelity are critical when making decisions about what to adapt [36]. In a systematic review by Gearing and colleagues of 24 meta-analyses and review articles focusing on fidelity over the past 30 years, the authors identified core components of fidelity including design, training, and monitoring of intervention receipt and suggested that greater attention is needed to document threats to fidelity that remain underreported [37]. While this is true for any implementation effort, it is even more important to consider when making and reporting adaptations. Of particular note in our findings, while many authors reported changes to the delivery of the EBI, including who delivered it, there were fewer who reported adapting training or monitoring of that delivery.

Although cultural modification is not part of Stirman’s taxonomy of adaptation modifications, we found that almost 75% of the authors described their adaptation in this way. Because cultural adaptations would almost always require some adaptation related to population and context, it is likely that authors in the Stirman review reporting adaptations to content, context, and new populations were, at least in some cases, making cultural adaptations. More clarity in definitions of what is meant by each type of adaptations is needed.

Our review uses a new taxonomy of steps or tasks for adaptation derived from a scoping study of existing frameworks [23]. We looked for nine steps or tasks and found that two adaptations reported all of the steps [38, 39], with the mean number being seven. Thus, most adaptation teams completed the majority of the steps. Overall, we found that most reported community assessment, preparation of materials, implementation, evaluation, and engaging stakeholders/experts as part of a program planning process. The least common step was selection of the EBI. This may be because some program staff may have already decided on the EBI a priori and did not undertake a process to review candidate EBIs and select one.

The Escoffery classification from a review of adaptation frameworks seems applicable to real-world adaptation and could be used by others as a taxonomy for describing adaptation steps [23]. However, there are details that may be nuanced that are important to understand for the field both in describing adaptation steps and for informing future adaptations of the same EBI. For example, some reports include information about which components of the intervention were pilot tested and what decisions were made based on assessment finding, who the stakeholders were, and how they were engaged. Additionally, specific details about who is involved in the adaptation process (stakeholders, target population, program deliverers, health promotion, and behavioral scientists) and who makes the final decisions on what changes to make are critical to document. This information could be very important in interpreting reasons for specific adaptations and informing subsequent ones for future EBI implementation.

Capacity building efforts can assist practitioners to document the process in more detail and be deliberative or proactive with adaptations. The Cancer Prevention and Control Research Network (CPCRN) has modules on program selection of EBIs and adaptation with tools that help practitioners to document the discussion and decisions related to those processes in their Putting Public Health Prevention into Practice training [40]. In addition, the new online decision support tool, IM ADAPT, walks public health professionals through a systematic process to create a logic model for the adapted EBI and a selection adaptation, implementation, and evaluation plan based on intervention mapping [41, 42].

Among those reports that included an evaluation, the most common outcomes were acceptability, fidelity, and feasibility. This is not surprising since acceptability and feasibility of an intervention is often associated with program adoption [27]. Only one third reported the use of an adaptation framework to inform their process. This number is surprisingly low. Adaptation frameworks would provide guidance and rationale for this process and should be used. Many frameworks exist, but perhaps program planners may not be aware of them [34] or may not know how to follow them without training or technical assistance. Due to the limited research on program adaptation, there also may not be the emphasis on adaptation models and frameworks. There needs to be increased dissemination and education on these frameworks to offer assistance with recommended steps in program adaptation.

This review offers a practical examination of adaptation across multiple programs and program types that were  implemented in community settings. It reports systematically on reasons for adaptation, types of modifications, and steps of adaptations for public health EBIs in public health practice. Adaptations are occurring in natural settings for a variety of reasons, and commonly, adaptations are made to intervention content or context. A few steps were used across adaptation teams in the process of adaptations, but the science of adaptation is still an emerging area of study in implementation science. More critical appraisal of intervention adaptations and their outcomes could assist with EBI transferability to increase the scale up and spread of EBI to increase population health impact.