A randomized controlled trial examining consumers' perceptions and opinions on using different versions of a FoodFlip© smartphone application for delivery of nutrition information.

Background: Food labelling is a common intervention to improve diets, where the back-of-pack Nutrition Information Panel (or Nutrition Facts table (NFt)) provides comprehensive nutrition information on food packages. However, many consumers find it difficult and time-consuming to identify healthier foods using the NFt. As a result, different interpretative nutrition rating systems (INRS) may enable healthier food choices and it is essential that consumers have the tools to allow for easily accessible nutrition information. The objective of this study was to examine consumers' perceptions of different (INRS) for delivery of nutrition information using different versions of a smartphone app, FoodFlip©.

Methods: This study was part of a larger randomized controlled trial examining consumer perceptions of different INRS on food products. A nationally representative commercial sample of 2008 Canadians were randomized to one of four INRS intervention groups: 1) traffic light, 2) health star rating, 3) 'high-in' warning labels or 4) no INRS (NFt only; control) and asked to scan or enter 20 products into FoodFlip© from a list of food products provided to them with varying levels of healthfulness. After completing the app task, participants were asked a series of 7-point Likert-scale and open-ended questions to provide opinions on the usability and functionality of the app.

Results: Of the survey sample of 1997 participants, 95% (n = 1907) completed the app task, with similar number of participants in each treatment group. The mean age was 40 ± 12 years with no differences in sociodemographic characteristics between treatment groups. The health star rating ranked significantly lower in comparison to the other treatment groups in terms of usefulness (OR, 95% CI -0.67, 0.52-0.85), believability (0.59, 0.46-0.75), and understanding (0.55, 0.44-0.71) (p < 0.001). The health star rating (1.20, 0.94-1.53) and control (NFt) (1,1,1) ranked significantly lower than the traffic light or the 'high-in' warning labels for their ability to compare the healthfulness of products (p < 0.001).

Conclusion: This study demonstrated Canadian consumers' preference for a nutrient-specific system (i.e. traffic light or 'high-in' warning labels). The app, which was liked by majority of the participants for its functionality and usability, has the potential to support healthy dietary decision making and may also encourage reformulation.

Trial Registration: NCT03290118 (Clinicaltrials.gov).