Table 1 Definition of terms used in the review

Implementation

 The varied aspects and means by which an intervention (or programme) is integrated into one or a number of organisations. Implementation is the critical gateway between an organisational decision to adopt an intervention and the routine use of that intervention; the transition period during which individuals become increasingly skilful, consistent, and committed in their use of an intervention.

 Adapted from Damschroder et al. [41]

Health promotion programme

 To distinguish our focus from broad, often national, policies and programmes, we defined school health promotion programmes as a designated combination of activities, learning materials, and messages which:

• are intended to achieve specific health promotion, health education, or healthy behaviour goals in pupils

• can be adopted and adapted within schools (e.g. whole years or classes)

• involve the dedicated time of pupils within school in order to participate in or learn from the programme

 Such programmes may have been developed within a school or as part of a wider (e.g. research-based) initiative. They could be delivered in particular lessons or times within the school day (e.g. Personal, Social and Health Education lessons), before or after school (e.g. after-school gardening club), or have their messages and learning materials delivered within the lessons of other subjects.

Realist review terms

 Adjudicate—To make a judgement about methodological quality or applicability in this instance and account for this judgement based on findings from the use of the critical appraisal tool or an explicit argument about why a piece of evidence was not applicable

 Consolidate—To bring together. In a realist synthesis, ‘to bring together into a more coherent whole’

 Context—The wider configuration of factors, not necessarily connected to a programme, which may enable or constrain the operation of specific mechanisms

 Juxtapose—To place two or more things (evidence fragments) together, especially in order to suggest a link between them or emphasise the contrast between them

 Mechanism—The way in which a programme’s resources or opportunities interact with the reasoning of individuals and lead to changes in behaviour

 Programme theory—A model linking outcomes to programme activities and the underlying theoretical assumptions of a programme or intervention [20]. These models contain, even if they do not explicitly state, ideas about how a problem can be best addressed and how factors that may undermine the actions of a programme can themselves be addressed [24]

 Reconcile—To make two or more apparently conflicting things (evidence fragments) consistent or compatible

 Situate—To place something (a piece or pieces of evidence) in a context or set of circumstances and show the connections (between it/them and other evidence fragments)