Table 4.

Summary of the main results and implications for future research.

Results	Implications for future research
Voice-based data collection is technically feasible.	Future studies are needed to understand the strengths and limitations of different voice interfaces.
Conversational interface was a frustration for users because it could cut out (eg, owing to a poor internet connection) and the conversation would have to start from the beginning.	Design a less conversational voice interface.
Alexa more suited to entering short bits of information.	Integration with a phone app would allow supplementing information to be entered with voice entries.
The majority of the Alexa entries (357/588, 60.7%) contained the same food or drink information as the corresponding web entry, but a substantial proportion contained differences.	Trial and compare different voice-based systems such as the Google Assistant.
Matching voice entry with corresponding web form entry was difficult and many could not be matched (and therefore compared).	Use a phone app to evaluate the collected data by asking participant to validate the entry, either marking the entry as correct or providing a correction.