Abstract
BACKGROUND: There are few examples of public health programmes rooted in system dynamics methodology. The aim of this paper was to broaden the evidence-base on the implementation and evaluation of a system dynamics programme for obesity prevention, using the Lifestyle Innovations based on youth's Knowledge and Experience (LIKE) Programme as a case study. In LIKE, system dynamics principles were operationalized around three central pillars: the action programme is (1) rooted in a system-based understanding; (2) integrated in the local context and (3) dynamic. METHODS: This study took place in an urban setting in Amsterdam, the Netherlands, as part of the LIKE programme. The action programme consisted of establishing thematic action groups around previously identified leverage points within the system of overweight-related behaviours among adolescents. An action monitoring register was used to monitor action development and implementation, including the targeted system level. To track action implementation and adaptation over time, we conducted an in-depth evaluation using ripple effects mapping and additional interviews for three action groups. This data was analysed by performing a thematic content analysis. RESULTS: During the 6-year course of LIKE, 63 action ideas were formulated by 12 action groups, and 22 of these actions were implemented. Most of these implemented actions targeted lower system levels. A total of 9 of the 22 implemented actions were incorporated in existing initiatives. We observed that operationalization of system dynamics principles influenced the form of the action programme. Action ideas were dynamic in the sense that they changed over time or were abandoned because of growing system insights and/or factors within the wider context. This required shifting the focus from individual actions to the programme as a whole and formulating action ideas in terms of their function in changing the system, instead of on its form. CONCLUSIONS: Using LIKE as a case study, this study provides an example of the output of a system dynamics action programme. We show how leverage points can be used as a starting point to develop action ideas that target lower and higher system levels. This demands monitoring and evaluation that facilitates continuous customization of the programme.