Emily Kothe - ICBM2012 - Randomised controlled trial of a theory-based intervention promoting fruit and vegetable consumption
Randomised controlled trial of a theory-based interventionpromoting fruit and vegetable consumption Emily Kothe & Barbara Mullan
Background• Increasing fruit and vegetable consumption leads to decreased risk of serious illness.• Young adults eat less fruit and vegetables than any age group.
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.
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
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.
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.
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.
The Fresh Facts EvaluationAcross both groups, significant increases in:– Subjective norm– Perceived behavioural control– Intention– Fruit and vegetable consumption Between baseline and follow-up
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
The Fresh Facts Evaluation• Female: 75%• Living with parents: 76%• Identified primary ethnicity as: – Australian: 38% – Northeast Asian: 27% – Southeast Asian: 12%
The Fresh Facts Evaluation Attitude Subjective Norm Perceived Behavioural ControlProvide general Provide information Arguments to bolsterinformation on the about others’ behaviour self-efficacyhealth-behavioural linkProvide general Provide information Provide instructioninformation on the about others’ approvalmaterial consequencesof behaviour
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