Researchers need to think very carefully before exposing people to misleading information in an online study, because it raises ethical, methodological, and practical challenges that are easy to underestimate.

Core ethical principles

When designing such a study, researchers should anchor everything in standard research ethics:

  • Minimise harm: Misleading information can shape beliefs and behaviour, especially around health, politics, finance, or safety; studies should avoid more than minimal risk and never worsen participantsā€™ real-world vulnerability.
  • Justify the deception: Deception or withholding information should only be used when it is scientifically necessary and there is no reasonable non-deceptive alternative.
  • Respect autonomy: Even when full details cannot be given, consent forms should still explain the general nature of the study, that some information is not fully revealed until afterward, and any reasonably foreseeable risks.
  • Social responsibility: Studies should not contribute to the broader misinformation ā€œecosystemā€ or weaken public trust in research or institutions.

A simple check: if participants knew about the misleading element beforehand, would many of them reasonably refuse to take part? If yes, an ethics committee is likely to see this as crossing a line.

Special online challenges with misleading information

Online settings add constraints that are less of a problem in lab studies:

  • Uncertain debriefing: Researchers often cannot guarantee that every participant reaches the end of the survey and actually reads and understands the debrief that corrects the misleading information.
  • Undoing the manipulation: Participants can open a new tab, search the ā€œfactā€ you presented, and discover it is false, effectively cancelling or distorting the manipulation.
  • Bots and low-quality responses: Automated accounts or careless human respondents may ā€œcompleteā€ the study but do not genuinely process the misleading content, making it hard to know whether the manipulation worked at all.
  • Viral spillover: Screenshots or links can be shared in other spaces, unintentionally spreading the misleading information beyond the research context.

These realities mean that procedures which are ethically and methodologically acceptable in a lab may not translate directly to online research.

Designing consent, deception, and debrief

Researchers need to design the entire participation flow around consent + controlled deception + effective correction.

Before the study (consent)

  • Use ā€œauthorised deceptionā€ where possible: Tell people that some aspects cannot be fully explained until afterwards, and that they will receive a full explanation and have the option to withdraw their data.
  • Describe risks in general terms: For example, say that the study involves exposure to potentially inaccurate statements and that you will later clarify what was true or false.
  • Avoid deceiving about risk or voluntariness: Ethics guidance generally forbids deception about any element that would reasonably affect someoneā€™s decision to participate (e.g., health risks, data use, coercion).

During the study (presentation of misleading information)

  • Proportionality of risk: Avoid using misleading information that could realistically change high-stakes behaviours (e.g., ā€œX cures cancerā€ or ā€œY is a guaranteed investmentā€).
  • Limit exposure: Use the minimum amount of misleading content required to answer the research question; consider masking it among clearly neutral items to reduce impact.
  • Attention vs. contamination: While attention checks are important, they can change how people read and interpret misleading information, so they must be chosen carefully and justified.

After the study (debrief and correction)

  • Strong, clear debrief: Provide a detailed explanation that explicitly labels which statements were misleading, why deception was used, and what the true information is.
  • Ensure comprehension: Because you canā€™t rely on everyone reading one final page, consider layered debriefing: on-screen message, emailed summary, and downloadable information with clarifications and credible sources.
  • Allow data withdrawal: Give participants an option, after full debriefing, to withdraw their data if they are uncomfortable with the deception.
  • Consider follow-up: For sensitive or consequential topics, a later reminder or correction (for example via email) can help ensure that the true information is what ā€œsticksā€ in memory.

Safeguarding data, privacy, and platforms

Online studies about misinformation almost always involve digital trace data and platform constraints.

  • Data protection: Follow recognised research integrity and data protection standards (anonymisation, secure storage, limiting re-identification risks).
  • Public vs. private spaces: Researchers should not assume that everything online is ā€œpublicā€; they should familiarise themselves with the context and work with moderators or administrators where relevant.
  • Platform policies: Some platforms restrict posting false content, even for research; violating these rules can harm participants and damage trust and may have legal consequences.
  • Researcher responsibility: If a study surfaces harmful content (e.g., self-harm threats or criminal activity), protocols should define when and how to report or respond.

In 2026, many institutions and journals expect explicit discussion of these issues in ethics submissions and methods sections, especially for studies about misinformation.

Validity threats and practical design tips

Beyond ethics, misleading information online easily undermines the very validity of the study. Key threats:

  • Participants fact-checking: Search engines or social media can reveal the deception mid-study, leading to demand characteristics, confusion, or selective dropout.
  • Non-human participants: Bots and automated tools can ā€œinflateā€ sample size without being influenced by the manipulation, contaminating the data.
  • Misunderstood manipulations: Poorly designed attention or logic checks may unintentionally teach participants that some items are suspicious or may change their reading strategy.

Practical strategies:

  • Use subtle manipulations: For example, small framing differences or ordering changes, rather than obviously false claims that beg to be Googled.
  • Layered quality checks: Use multiple indicators of genuine engagement (completion time, response consistency, embedded comprehension questions) but ensure they are not so revealing that they expose the deception.
  • Pilot carefully: Run small pilots to see how often participants search for information, share the materials, or drop out at particular points; adjust design accordingly.

The central ā€œconsiderationā€ in a sentence

If you need a single-sentence answer to the original exam-style question:

Researchers must recognise that, in an online study with misleading information, they cannot guarantee that participants will reach, read, and understand the debrief that corrects the deception, so the entire design must account for this limitation (and related issues like fact-checking, bots, and attention checks).

TL;DR:
When designing an online study that presents participants with misleading information, researchers must rigorously justify the deception, minimise harm, plan strong and realistic debriefing procedures, and account for online- specific complications such as participants fact-checking the manipulation, bots contaminating data, and the risk that participants never see or understand the corrective information.