Improving children’s dietary intake: mapping behaviour change techniques onto the Change4Life Food Scanner app

Despite the growing rise in dietary digital interventions, the majority are not evidence-based. The Change4Life Food Scanner app was designed to raise awareness of the nutritional content of packaged foods. The app has undergone multiple changes since its release including content and design feature updates. To understand its intended mechanism of behaviour change and how evidence-based behaviour change techniques (BCTs) or strategies evolve with app updates, this research aimed to map out and compare BCTs of two versions of the Change4Life Food Scanner app. This will provide insight into the use of potentially effective BCTs within behavioural interventions and inform future app development. Two independent coders undertook a descriptive comparative analysis of the use of BCTs in two versions of the Food Scanner app using the BCT Taxonomy. Results showed that the outdated version consisted of eight BCTs, whilst the updated version consisted of eleven and was comparatively more BCT intensive in terms of content and occurrence. Both versions incorporated ‘goal setting (behavior)’, ‘feedback on behavior’, ‘social support (unspecified)’, ‘instruction on how to perform behavior’, ‘salience of consequences’, ‘prompts/cues’ and ‘credible source’. Almost 70% of the BCTs used in the Food Scanner app have previously been found to be effective for changing behaviour. However, who uses the app and how the app is used could impact on the exposure and effect of BCTs on dietary intake. Future work to evaluate the effectiveness of the app is recommended to provide insight into whether the combination of BCTs used are effective in improving children’s diets.