Oral Presentation Australian and New Zealand Obesity Society Annual Scientific Conference 2023

Formative and impact evaluation of a social marketing campaign to address unhealthy dietary behaviours  (97809)

Rebecca Godwin 1 , Belinda Morley 1 2 , Elizaveta Ilchenko 1 , Rachael Jinnette 1 , Michael Murphy 3 , Ellen Hart 4 , Monique D'Souza 4 , Ainslie Sartori 4 , Helen Dixon 1 5
  1. Centre for Behavioural Research in Cancer, Cancer Council Victoria, East Melbourne
  2. Melbourne School of Population and Global Health, The University of Melbourne, Parkville
  3. MMResearch, Melbourne
  4. Cancer Council Western Australia, Subiaco, Western Australia
  5. Melbourne School of Psychological Sciences, The University of Melbourne, Parkville

Background: LiveLighter® is a healthy lifestyle public education program, launched in Western Australia (WA) in 2012. Formative evaluation is consistently undertaken to pre-test campaign concepts with the target audience. Testing in August 2020 resulted in two new campaigns being developed, implemented, and evaluated: ‘Menu App’ - to raise awareness of risks of regularly consuming fast food ordered using online food delivery (Mar-May 2021), and ‘Reverse’ - to decrease negative, and increase positive, dietary behaviours (Sep-Dec 2022).  

Methods: Formative evaluation pre-tested campaign concepts using six focus groups with WA adults segmented by sex, location (metro, rural) and age for the metro groups (25-34, 35-49). Impact evaluation utilised a controlled cohort design with baseline population surveys (approx. N=1,500 per state) of 25-49-year-olds in WA (campaign state) and South Australia (SA: comparison state) with participants followed-up post-campaign.  

Results: Formative evaluation: The strongest performing creative concept for addressing the communication objective of increasing knowledge was ‘Reverse’, while for changing behaviour ‘Menu App’ performed best. Impact evaluation: Following ‘Reverse’, awareness of the link between excess body fat and cancer (sugary drink consumers: WA 57%-66% cf. SA 58%-52%, interaction; p=.005; WA campaign exposure: 75% cf. WA no exposure: 67%, p<0.05) and concern about sugary drink intake (WA campaign exposure: 41% cf. WA no exposure: 32%, p<0.05) increased. Following ‘Menu App’ there were significant decreases in fast food consumption (WA: 35%-29%; SA: 33%-34%; interaction p=.062) and ordering online (WA: 54%-48%; SA: 54%-53%; interaction p=.076), while consumption of homemade meals significantly increased (WA: 39%-45%; SA: 41%-42%; interaction p=.158). 

Conclusions: The ‘Reverse’ campaign improved knowledge and awareness of health risks, while ‘Menu App’ positively impacted dietary intentions and behaviours. Impact evaluation findings align with formative evaluation findings, highlighting the importance of pre-testing social marketing campaign communications to maximise their potential to impact the target audience as intended.