- Alexander M Clark, professor 1,
- Thomas G Briffa, research associate professor2,
- Lorraine Thirsk, assistant professor3,
- Lis Neubeck, senior research fellow4,
- Julie Redfern, senior research fellow4
- 1Faculty of Nursing, Clinical Sciences Building, University of Alberta, Edmonton, AB, Canada T6G1C9
- 2School of Population Health, University of Western Australia, Crawley, WA, Australia
- 3Faculty of Nursing, University of Alberta, AB, Canada
- 4George Institute for Global Health, University of Sydney, Sydney, NSW, Australia
- Correspondence to: A M Clark
Who would you rather have as a player on your football team: Messi or Clark⇓? Both players share numerous characteristics, such as they both have brown hair, have the same size feet, and are less than 6 ft (1.8 m) tall. Each has scored many goals, playing in the number 10 jersey.
However, focusing on these overt characteristics is not a good basis for decision making. Close observation, informed assessment, and knowing the context of previous successes (goals against whom and on what occasion) provide more useful insights into the determinants of success in football. Lionel Messi, the Argentinean international professional player, is infinitely preferable to Alex Clark, an amateur from the University of Alberta, Canada. Yet research into complex healthcare interventions still focuses on easily described components of interventions and risks overlooking what really matters.
Complex versus complicated
Interventions in football and healthcare systems are “complex” rather than “complicated.”1 Phenomena are complicated when intervention outcomes can be reliably predicted from past behaviour with the help of mathematical analysis. Sending a rocket to the moon is complicated.2 However, phenomena are complex when too many factors are interacting. In such situations formulas have limited application and similar past experience is a poor predictor of future success.2 Raising a child is complex—doing the same things at different times often results in quite different outcomes.2 Accordingly, in football, formula driven approaches have consistently failed,3 and a health intervention that succeeds in one setting may have very different results in another.
Complex interventions in football and healthcare have a range of shorter term and longer term outcomes (table 1⇓) and …