Intervention (Hidden)
Phase I: Bias measurement & correction
Our intervention consists of two parts. First, we show the evidence of their own cognitive biases. Second, we provide practical tips and hints to help them become more aware and critical when processing information. Similar frameworks have been used in other studies across different contexts (Pham et al., 2024; Devine et al., 2012; Rahmawati & Santi, 2023) where raising awareness of the problem is considered an essential first step, followed by offering strategies to address it.
In the first part of the treatment, we address the existence of biases by showing the examples from the bias-related questions that participants have just answered. Specifically, we ask two sets of questions designed to reveal anchoring bias and availability bias. For anchoring bias, we follow the procedure outlined by (Berthet et al., 2022; Berthet, 2021) and for availability bias, we follow (Pachur et al., 2012). These questions are to elicit the presence of bias and help participants see its relevance before we provide the information intervention. During the first part of the intervention, we remind participants that we used techniques such as numerical anchoring or priming (e.g., mentioning a “traffic accident”) to influence their answers. By explicitly revealing these techniques, we encourage participants to reflect on how their responses may have been shaped by such cues and to reconsider their initial judgments.
In the second part of the treatment, our main goal is to raise awareness of the existence of cognitive biases and educate individuals on general tools to reduce them. We do not focus on any single type of bias. Since no single debiasing strategy works for all types of biases (Croskerry et al., 2013), we take a broader approach by promoting critical thinking through an educational video intervention. Critical thinking strategies have been widely used in previous research to reduce bias (Smith & Peloghitis, 2024; Croskerry et al., 2013). In our intervention, we provide practical tips to encourage critical thinking in the context of online media consumption. For instance, we suggest that people pause before sharing information, or prompt them to use their existing ability to critically evaluate content (e.g., by checking multiple sources or talking to others) (Tang & Sergeeva, 2025). We chose a video format for our intervention to ensure consistent delivery of information to all participants, following recommended guidelines (Haaland et al., 2023). This approach is more effective in conveying the messages and avoid the potential inconsistencies that may occur if using in-person training.
For the placebo intervention, we designed a video that provides tips for participating wedding or anniversary parties. The placebo and treatment videos were kept the same length.
Phase II: Nudging
To reinforce the treatment message and encourage retention, participants in the treatment group will receive short reminder messages via SMS or Zalo every two weeks. Each message will briefly restate key points from the intervention (e.g., pausing before sharing, verifying information sources) and include a link to rewatch the 4-minute instrumental video. These reminders are designed to maintain awareness of safe online behaviors and strengthen the long-term effect of the bias-correction intervention.
Reference:
Berthet, V. (2021). The measurement of individual differences in cognitive biases: A review and improvement. Frontiers in Psychology, 12, 630177.
Berthet, V., Autissier, D., & de Gardelle, V. (2022). Individual differences in decision-making: A test of a one-factor model of rationality. Personality and Individual Differences, 189, 111485.
Croskerry, P., Singhal, G., & Mamede, S. (2013). Cognitive debiasing 2: Impediments to and strategies for change. BMJ Quality & Safety, 22(Suppl 2), ii65–ii72.
Devine, P. G., Forscher, P. S., Austin, A. J., & Cox, W. T. (2012). Long-term reduction in implicit race bias: A prejudice habit-breaking intervention. Journal of Experimental Social Psychology, 48(6), 1267–1278.
Haaland, I., Roth, C., & Wohlfart, J. (2023). Designing information provision experiments. Journal of Economic Literature, 61(1), 3–40.
Pachur, T., Hertwig, R., & Steinmann, F. (2012). How do people judge risks: Availability heuristic, affect heuristic, or both? Journal of Experimental Psychology: Applied, 18(3), 314.
Pham, T., Goto, D., & Tran, D. (2024). Child online safety education: A program evaluation combining a randomized controlled trial and list experiments in Vietnam. Computers in Human Behavior, 156, 108225.
Rahmawati, F., & Santi, F. (2023). A Literature Review on the Influence of Availability Bias and Overconfidence Bias on Investor Decisions. East Asian Journal of Multidisciplinary Research, 2(12), 4961–4976.
Smith, G., & Peloghitis, J. (2024). Approaching Cognitive Bias in Critical Thinking Instruction. JALT Postconference Publication, 2023, 339–346.
Tang, H., & Sergeeva, A. (2025). Shots and Boosters: Exploring the Use of Combined Prebunking Interventions to Raise Critical Thinking and Create Long-Term Protection Against Misinformation (No. arXiv:2505.07486). arXiv. https://doi.org/10.48550/arXiv.2505.07486
Thomson, K. S., & Oppenheimer, D. M. (2016). Investigating an alternate form of the cognitive reflection test. Judgment and Decision Making, 11(1), 99–113.
Zhang, Z., & Cheng, Z. (2024). Users’ unverified information-sharing behavior on social media: The role of reasoned and social reactive pathways. Acta Psychologica, 245(October 2023), 104215. https://doi.org/10.1016/j.actpsy.2024.104215