A Novel Protocol for an Experimental Epidemic Game to Study Quarantine Behavior Dynamics: The Epi-Q Study

Background: We describe the protocol for the Epi-Q (EpiGame-Quarantine) Study, using an experimental epidemic game (“epigame”) to investigate quarantine-related attitudes and behaviors. Epigames are field experiments in which participants make behavioral decisions during a simulated epidemic in naturalistic settings. In this study, the epigame is operationalized via a smartphone app that simulates transmission of a 'digital pathogen' over Bluetooth, allowing for real-time data capture. This approach offers a novel tool for observing decision-making within social networks under dynamic risk and normative pressure. Consequently, it enables the collection of empirical data on the social, psychological, and practical determinants of compliance with non-pharmaceutical interventions, such as quarantine. Unlike existing methods that rely on static cross-sectional surveys or observational data, Epi-Q captures dynamic decision-making within real-life networks. This is crucial for studying behaviors like quarantine, where compliance is not merely an individual calculation but is shaped by pre-existing and evolving social structures, including peer pressure, trust in institutions, and exposure to misinformation. Epi-Q employs a quantitative mixed-method design to untangle the complex interplay between social norms and risk perception, along with their interactions on behavioral responses. Methods/design: We will recruit at least 150 participants via a custom-made smartphone app capable of measuring proximity between then using Bluetooth. We will randomly allocate these participants (via network-aware clustering) into a 2×2 experimental design: (i) local vs global risk information; (ii) local vs global norms. ‘Local’ information is defined as data derived from a participant's first-degree contacts in the Bluetooth proximity network, while 'Global' information refers to aggregate data from the entire experimental group. Participants will play the epigame over a period of several weeks (one to three), making daily quarantine decisions within the app that incur costs (loss of in-game points for infection, loss of opportunities while quarantining) and benefits (points from remaining active), while Bluetooth proximity sensing samples the contact network of participants and drives simulated transmission of a digital pathogen among the phones. Data collection will include in-app behavioral logs, pre- and post-game surveys (attitudes, risk perception), and optional qualitative debrief interviews with a subset of participants. Primary outcomes will be frequency and timing of quarantine adoption; secondary outcomes will include attitudinal shifts, perceived risk, and the consistency of real-world vs in-game intentions. Analyses will include mixed-method synthesis, difference-in-differences modeling, social network analysis, and correlation of survey and behavioral measures to assess external validity.