Sustaining Implementation or Implementing Sustainability? Understanding the Implementation and Sustainability of Community-based Public Health Programmes

Abstract

Although it is now recognised that the way a public health programme is implemented affects its outcomes, there is little agreement on what successful implementation means, and there is a paucity of information on how these programmes are sustained. In this thesis, I investigate the implementation processes of these programmes and how they are sustained. The thesis is developed from a synthesis of the findings from four linked studies; a systematic review, an observational study, an interview study and an analysis of secondary questionnaires from a school-based peer-to-peer smoking prevention programme called the ASSIST. I conclude that the implementation of community-based public health programmes is characterised by interactive stages of the implementation process, namely, 1) pre-implementation activities, 2) the process of adopting the programme, 3) the actual implementation, 4) any necessary adaptations to the programme and 5) sustainability. These stages influence each other and they feedback onto the process. In addition, the process of implementation is influenced by its social-cultural environment, and it is characterised by nine aspects namely; adaptation, participant responsiveness, fidelity, dose received/delivered, quality of delivery, programme differentiation, reach, theory, and programme design. However, the sustainability of the programme is not only an end-stage or an outcome of the implementation process, it is also a process in itself and it evolves when mechanisms of sustainability interact with a progressing process of implementation. The mechanisms of sustainability are attributes of the intervention namely; Credibility, Simplicity, Marketability, Contextualisability, and justifiability of the intervention, plus a consistency of these attributes. In sustained programmes, these mechanisms interact with progressing stages of implementation and this results in the emergence of a typology of sustainability namely; 1) potential sustainability (present at trial and during the adoption stage), 2) foundational sustainability (emergent during adoption and implementation), 3) operational sustainability (emergent during implementation and adaptation) and 4) actual sustainability (the end product). The mechanisms are interactive, e.g. marketability enhances contextualisability, while simplicity and credibility supports justifiability and justifiability enhances the ultimate sustainability status of the programme. At the same time, the attributes are most crucial at varying stages, so credibility and simplicity are crucial at adoption while contextualisability and marketability are most important during implementation. Justifiability is crucial for maintaining the implementation, but like all other theories, it is also required throughout the entire process (consistency). These findings represent a new conceptualisation of implementation and sustainability, and they could contribute to the development of a potential general theory of implementation and sustainability.