Picture this! The influence of stressing the camera feature in the mail invitation to an app-based household budget survey on participation behavior

RELEVANCE & RESEARCH QUESTION Diary-based household budget surveys are often burdensome, as respondents must manually log details (e.g., product type, quantity, price) for each purchase over time. A smartphone app that allows participants to upload photos of shopping receipts could reduce this burden and increase survey participation. However, requiring an app that accesses the camera may raise privacy concerns, potentially affecting willingness to participate. This study investigates the influence of highlighting the app’s camera feature in the invitation on both response rates and camera usage in the diary. METHODS & DATA In November 2024, a sample of over 7,000 individuals in Germany who’s addresses were drawn from residents’ registration office lists were invited to participate in a smartphone-based household budget survey. Invitation letters included a QR code, URL, and personalized login credentials for the AusgabenAtlas app, compatible with Android and iOS devices. Participants were asked to log their daily spendings in a two-week diary, with the option to use the camera function for receipt uploads or input data manually. Sample members were randomly assigned to one of three invitation treatments that varied in how the camera feature was framed: (1) no mention of the camera feature, (2) mention of the camera feature, and (3) mention of the camera feature with additional emphasis on the effort required. RESULTS Data collection will conclude in December 2024, with preliminary findings available in January 2025. We will examine the effect of the invitation treatment on survey response rates and camera feature usage within the app.