How evidence informed decision-making can take a systems perspective: the implications of systems thinking for public health evaluation

Elizabeth McGill (1,4) and Mark Petticrew (1,2,3,4)

The past twenty years have seen a rapid rise in interest in complex interventions and their evaluation. This has partly been driven by a perception that many interventions within and outside the health sector are complex. This is often defined in terms of their being (i) multicomponent (that is, the intervention itself may comprise multiple components that may interact in synergistic ways), (ii) non-linear (they may not bring about their effects via simple linear causal pathways); and (iii) context-dependent (they are not standardised, but may work best if tailored to local contexts). However in recent years a different (but complementary) perspective has begun to gain traction in public health. This sees interventions not as discrete, bounded activities (as in the case of “complex interventions”), but as interconnected “events in systems”.

This seminar will discuss the implications of a “systems perspective” (as opposed to an “interventions perspective”) for public health research, with a focus on evaluation: how interventions may be evaluated, and how evidence might be reviewed from a systems perspective. It will use examples from the presenters’ research on food and alcohol systems.

The slides are available here >>

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1. Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine (LSHTM)
2. Policy Innovation Research Unit, LSHTM
3. Public Health Research Consortium, LSHTM
4. NIHR School for Public Health Research, LSHTM