Emily Kothe - ICBM2012 - Randomised controlled trial of a theory-based intervention promoting fruit and vegetable consumption
1. Randomised controlled trial of
a theory-based intervention
promoting fruit and vegetable
consumption
Emily Kothe & Barbara Mullan
2. Background
• Increasing fruit and vegetable consumption
leads to decreased risk of serious illness.
• Young adults eat less fruit and vegetables
than any age group.
3. What is Fresh Facts?
• Web-based intervention to increase fruit
and vegetable consumption in young adults
– Email delivered intervention
– Based on the Theory of Planned Behaviour
– 30 day intervention program – with emails every 3
days.
4. What is Fresh Facts?
• Content
– Was developed in pilot studies young adults
– Was based on the Taxonomy of Behaviour
Change Techniques
– Targeted attitude, subjective norm and
perceived behavioural control
5. The Fresh Facts Evaluation
Pilot work had suggested that Fresh Facts:
• Is acceptable to participants1 and results in
increases in fruit and vegetable intake
relative to baseline.2
• This study tested Fresh Facts using a more
robust RCT design.
1. Kothe, E. J., & Mullan, B. A. (in press). Acceptability and feasibility of an email-based nutrition intervention using the
theory of planned behaviour in Australia: Fresh Facts. Health Promotion International.
2. Kothe, E. J., Mullan, B. A., & Butow, P. (2012). Promoting fruit and vegetable consumption: Testing an intervention
based on the theory of planned behaviour. Appetite.
12. The Fresh Facts Evaluation
• The intervention lead to improvements in
attitude and subjective norm that were not
translated to changes in behaviour.
• Previous reports of intervention effectiveness
can be explained by changes not related to
Fresh Facts itself.
13. Implications
• More research is needed to understand
mechanisms behind control group change.
• Researchers may need to target more
proximal antecedents of fruit and vegetable
consumption to achieve change.
15. The Fresh Facts Evaluation
Across both groups, significant increases in:
– Subjective norm
– Perceived behavioural control
– Intention
– Fruit and vegetable consumption
Between baseline and follow-up
16. The Fresh Facts Evaluation
The intervention lead to increases in:
– Attitude and subjective norm
But not in:
– Perceived behavioural control
– Intention
– Fruit and vegetable consumption
17. The Fresh Facts Evaluation
• Female: 75%
• Living with parents: 76%
• Identified primary ethnicity as:
– Australian: 38%
– Northeast Asian: 27%
– Southeast Asian: 12%
18. The Fresh Facts Evaluation
Attitude Subjective Norm Perceived
Behavioural Control
Provide general Provide information Arguments to bolster
information on the about others’ behaviour self-efficacy
health-behavioural link
Provide general Provide information Provide instruction
information on the about others’ approval
material consequences
of behaviour
19. The Fresh Facts Evaluation
• Baseline:
– 2-item fruit and vegetable screener*
– Block FFQ*
– Demographics
– Theory of planned behaviour questionnaire*
• Follow-up
– Starred items repeated at 1 month