Promoting optimal nutrition is the central focus of public health nutrition (PHN) as a discipline. While some progress has been made internationally in addressing undernutrition, progress has been too slow to achieve the Millennium Development Goals(Reference Bryce, Coitinho and Darnton-Hill1, Reference Morris, Coghill and Uauy2). Overnutrition, as expressed by rates of overweight and obesity, is rising in most countries(3), with many low- and middle-income countries now suffering a double burden. Many countries have responded by developing policies and action plans that are aimed at addressing these major nutrition problems(Reference Lachat, Van Camp and De Henauws4), but they usually ignore issues relating to capacity to implement and the determinants of capacity such as workforce development(Reference Margetts5). As a consequence, many nutrition policies and plans are not being effectively implemented(Reference Nishida, Shrimpton and Darnton-Hill6). Building strategic and operational capacity is recognised as a critical determinant of the effectiveness of local, national and international nutrition systems in delivering optimal nutrition outcomes for populations(Reference Morris, Coghill and Uauy2, Reference Hughes7). As both forms of capacity are dependent on purposive and multi-strategy investments in workforce development at all levels in the system, workforce development remains an outstanding and often neglected challenge in our discipline area. Workforce capacity deficits in PHN are a universal problem, even in rich economies with well-developed health systems(Reference Margetts5, Reference Hughes7–Reference Haughton and George9). The key determinants of workforce capacity that are consistent internationally are summarised in Table 1.
Determinants of public health nutrition (PHN) workforce capacity(Reference Margetts5–Reference Haughton and George9, Reference Hughes17)
Of the determinants outlined in Table 1 that impact on workforce capacity, workforce preparation and practice improvement are most amenable to change within, and by, the PHN community.
Public health nutrition practice
PHN practice spans activities that range from academic and analytical work through to working ‘in situ’ with communities and stakeholders to address nutrition issues. A focus on assessing, strategically changing and evaluating the socio-economic, physical and cultural determinants of nutritional status affecting health characterises PHN practice(Reference Hughes10). As a result, PHN practice involves a complexity that creates significant challenges for the strategic development of the practitioner workforce and its effectiveness. This is exacerbated by changing practice paradigms in the field of nutrition(Reference Jonsson11), which makes it difficult to apply a comprehensive description of the nature of PHN practice across all practice settings. For the purposes of the present paper, PHN practice is defined as the work required to effectively develop, implement and evaluate interventions that address identified, population-based nutrition problems. In this context, intervention refers to actions that intentionally focus on changing health outcomes by addressing the determinants of nutritional exposures.
To date the PHN research literature has tended to apply an epidemiological focus on exploring and understanding the determinants and distribution of nutrition issues, and evaluation of interventions. This assumption can be tested by reviewing any issue of this journal. This work has been critically important in understanding what determinants cause nutrition problems, what strategies have merit in terms of producing desired changes in health status and how to measure these changes. Unfortunately, this literature does not provide adequate guidance about how to practise PHN effectively within specific contexts, what work is required and what competencies are required to effectively promote and maintain the nutrition-related health and well-being of populations.
Core functions and competencies
The lack of consideration of the practice of PHN constrains PHN workforce development, practice effectiveness and overall capacity(Reference Hughes12). This has prompted efforts to identify, assess consensus and codify the core functions of the PHN workforce; core functions being those considered absolutely necessary to ensure public health capacity(13). This has been done to help focus workforce development efforts in developed countries such as Australia and the European Union(Reference Hughes14–Reference Hughes16). This consensus development work has identified intervention management (the design, planning, implementation and evaluation of public health interventions) as a dominant core workforce function (with as much as 50 % of core functions identified reflecting intervention management practices), reinforcing earlier findings in Australia about employer expectations(Reference Hughes14) and workforce practices(Reference Hughes17). Capacity-building functions are similarly rated as core functions, reinforcing the long-held view of capacity building as an important strategic approach in developing country PHN practice(Reference Elmadfa18, Reference Shrimpton19).
If an understanding of the core functions (the work) of the PHN workforce is a prerequisite for strategic workforce development, there is a powerful logic in aligning core functions with the competencies required to perform these functions(Reference Hughes20); competencies here referring to the knowledge, skills and ‘ways of thinking’ required to effectively perform a work function(Reference Hughes, Shrimpton and Recine21). In practice, the competency mix required to effectively manage interventions and build capacity has been shown to be quite broad, drawing on a mix of analytical, management, strategic planning, leadership and organisational competencies(Reference Jonsdottir, Hughes and Thorsdottir22, Reference Hughes23). Unfortunately, there is limited scholarship about the most effective and efficient methods to develop these competencies in our disciplinary literature. To help address this gap, the present paper describes a new model for PHN intervention management practice designed to facilitate practice improvement and provide a step-wise approach to assist with PHN workforce preparation.
Step-wise processes to guide practice
Step-wise processes for practice and learning have been widely applied conceptual devices used to help bring order to this complexity in health practice and education. PHN practice borrows heavily from the related disciplines of health promotion, public health and dietetics, and has adopted many of the practice cycles that have evolved in these disciplines(Reference Margetts24), which are all loosely based on action research processes that include cycles of planning, acting, observing and reflecting(Reference Lewin25). Cyclical and systematic processes for intervention management and practice have been used for many years to inform strategic decision making and to enhance the quality and effectiveness of intervention management(Reference Godin, Gagnon and Alary26, Reference Ader, Berensson and Carlsson27). These have varied in terms of the degree of segmentation in the step-wise cycle. The Triple-A cycle(Reference Jonsson28) that includes three main steps of Analysis, Action and Assessment was developed to assist with interventions dealing with malnutrition. Intervention mapping was proposed in the late 1990s as a sequential process of integrating theory, empirical findings from the literature and information collected from the population to inform strategic decision making about how best to address health promotion challenges(Reference Bartholomew, Parcel and Kok29). Borrowing from these earlier models, the PHN cycle(Reference Margetts24) has been proposed as a seven-step practice cycle to describe the nature of PHN practice. This model replicates the basic cycle of needs assessment, planning, implementation and evaluation used in earlier health promotion planning models. Both of these earlier PHN practice cycles have more recently been adapted in an attempt to more explicitly integrate capacity-building principles and practice as part of the process of developing sustainable interventions(Reference Baillie, Bjarnholt and Gruber30).
As models for informing PHN practice and workforce development, we believe these earlier models have limitations in the context of workforce development and practice improvement in that they do not adequately deconstruct practice in a way that can inform responses to the ‘where do I start?’, ‘how?’ and ‘with who?’ type questions that are important in teaching students PHN practice competencies. They similarly do not reflect a notion of progress in practice (moving forward rather than going around-and-around), and they do not adequately integrate capacity-building strategies with project planning in a step-by-step sequence.
A bi-cyclic framework for public health nutrition practice
We propose a bi-cyclic model for PHN practice (‘the bi-cycle’; Fig. 1) over three distinct stages, to inform workforce development and practice in the core practice area of intervention management. This model recognises the progressive and cumulative nature of PHN practice (i.e. moving forward) and integrates capacity building into the planning–implementation–evaluation sequence. This practice framework emphasises the process, tools and rationale for practice approaches in PHN. To encourage discipline in PHN practice, it is intentionally pedantic in the way that it has deconstructed earlier models into what may seem to be overly numerous discrete steps, which are summarised in Table 1.
The bi-cycle framework for public health nutrition (PHN) practice(Reference Hughes and Margetts32)
Different phases in practice
The intelligence phase, represented by the first loop in the bi-cycle, forces practitioners to engage with their communities and key stakeholders and understand the problem and contextual factors before acting; intelligence in this context referring to information from various sources and methods that help inform decision making about intervention design. Understanding before acting means careful and varied analysis of the community, the community's capacity for action, the problems faced and what determinants have a causal relationship with the problem – the logic being that until ‘upstream’ determinants that need to be changed are identified, it is difficult to develop strategies that will lead to a change in ‘downstream’ health outcomes. The action phase of PHN practice, represented by the connection between the intelligence and evaluation loops in the bi-cycle, focuses on planning and managing intervention implementation. The evaluation phase in the PHN practice bi-cycle focuses on the different levels and types of evaluation, and emphasises the importance of sharing practice leanings via dissemination and scholarship.
Feedback between cycles
The backward arrow linking the action phase with evaluation and intelligence phases (the bi-cycle's chain) represents the dynamic nature of intervention management that regularly requires practitioners to go back to the intelligence, to fine-tune strategies and adapt to changing contexts in practice. It also illustrates that evaluation builds on the intelligence required to inform practice.
Improving practice
PHN practice, to be effective, needs to be dynamic, responsive and contextual to the setting, situation and available resources. Without an intentional and strategic emphasis on the capacity-building approach to practice, PHN practice and the resultant interventions are likely to produce disappointing returns on investment in terms of outcomes relative to resources used. The bi-cyclic model for practice provides a systematic process for intervention management that has applications irrespective of the issues being addressed, the practice context, the strategy mix and the level of intervention. It integrates capacity-building steps (steps 1, 3, 5, 6, 7, 15, 17) into the sequential practice cycle, making it an explicit approach to practice consistent with previous arguments about the need to bring capacity-building strategies to the forefront of PHN practice(Reference Baillie, Bjarnholt and Gruber30, Reference Labonte, Woodward and Chad31). Our proposition then is that this model, if applied in practice, will enhance practice effectiveness compared with earlier less integrated approaches and serve a useful practice improvement function.
Workforce preparation
We believe that the model has its greatest utility in the development of PHN practice competencies during workforce preparation, both in the pre-employment and post-employment (continuing education) stages of workforce development. We have previously used the bi-cycle model as a framework for curriculum development and instructional design in the courses and texts(Reference Hughes and Margetts32) we use to teach in our respective universities, as a framework for a PHN workforce mentoring intervention(Reference Palermo, Hughes and McCall33) and a suite of online learning modules has been developed as part of the JobNut Project funded by the European Union (http://www.medicine.tcd.ie/nutrition-dietetics/jobnut/). Each step provides an opportunity to engage students in learning and skill development regarding the rationale in practice, techniques and tools to assist with PHN practice in a sequential manner. We have used the model to guide students develop comprehensive PHN intervention plans as a basis for assessment and later practice-based implementation during professional internships. In the process, we believe we are preparing students to be employable, effective in practice and to be catalysts for change.
Table 2 aligns each step in the practice cycle with a summary of the competency elements derived from recently published PHN academic standards(Reference Hughes, Shrimpton and Recine21) required at each step and some of the learning and teaching strategies that can be used to build these competencies.
The bi-cycle framework for public health nutrition practice: aligning practice, competencies and learning and teaching strategies
*The World Public Health Nutrition Association competency standards framework categorises competency elements and performance indicators under thirteen competency module categories including: EK, enabling knowledge; NS, nutrition science; AN, analytical; PHSK, public health system knowledge; FNSK, food and nutrition system knowledge; NE, nutrition education; MGT, management; LDR, leadership; PROF, professional; COM, communication; NAMS, nutrition assessment monitoring and surveillance; CB, capacity building; IM, intervention management.
Learning and teaching rationale
From an androgogical (adult learning and teaching) perspective, the bi-cycle model provides a conceptual framework to structure experiential learning that reflects the key motivations for adult learning. These motivations include needing to know the reason for learning something, experience as a basis for learning, involvement in the planning and evaluation of their instruction, learning of immediate relevance to their work lives and learning that is problem centred(Reference Knowles, Holton and Swanson34). This approach goes beyond didactic teaching for knowing to teaching so that learners can ‘know how’, ‘show how’ and ‘do’(Reference Miller35). This model has an intentional focus on developing the meta-cognitive aspects of practitioner competency, including ways of thinking about problems and possible solutions, making decisions and reflecting on practice in order to continue learning and improving practice. It therefore can be an important part of the process of professionalisation required in the preparation and continuing education of PHN professionals. As Table 2 illustrates, the breadth of competency development opportunities that working through the bi-cycle step-wise process presents suggests it has potential as the basis for a comprehensive approach to PHN competency development as a curriculum component.
Conclusions
The bi-cycle model for PHN practice is proposed as a new framework for workforce development and practice improvement that builds on earlier models. As a conceptual model designed to assist a disciplined and sequential process for practice and learning, that integrates capacity building with intervention management, we have found it useful as a scaffold for learning interventions, competency development and critical reflection on PHN practice. The assumption that this model, if applied in practice, will more effectively enhance public health outcomes than other less systematic and intentional approaches to practice is yet to be substantially and objectively evaluated. This is currently a focus of ongoing work. We acknowledge that PHN practice is dynamic and varied, and that models need to be adaptable and applicable to practice context, to have utility. The present paper serves to stimulate debate in the PHN community, to encourage critical feedback about the validity, applicability and utility of this model in different practice contexts.
Acknowledgements
This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. There are no conflicts of interest. R.H. took the principal role in conceptualising the model and drafting and finalising the paper. B.M. contributed to model conceptualisation, paper drafting and editing. The development of the bi-cycle model has been assisted by feedback from many of our students over the past decade and input from our colleagues Christina Black, Jenny Davies and Nick Kennedy. The constructive suggestions from the reviewers have contributed to the fine-tuning of this paper, and are acknowledged.
