Why Cancer Patients Fall for Online Misinformation: New Interview Study Reveals the Triggers

A cancer diagnosis does not just launch a medical journey; it launches an information crisis. Within hours of hearing the word

The psychological weight of a cancer diagnosis creates conditions that researchers have long recognised as fertile ground for misinformation to take root. When patients and their families receive life-altering news, their cognitive resources are often stretched to breaking point. The study under discussion, conducted at King Fahad Specialist Hospital in Dammam, Saudi Arabia, captures this dynamic in striking detail through semi-structured interviews with nineteen cancer patients and six caregivers. By grounding their analysis in two well-established psychological frameworks, the theory of planned behaviour and the health belief model, the researchers moved beyond simply cataloguing what participants searched for online and instead examined the underlying beliefs that shaped how they searched, what they trusted, and why they sometimes fell prey to false or misleading claims.

The theory of planned behaviour posits that human actions are guided by three kinds of beliefs: behavioural beliefs about the consequences of an action, normative beliefs about the expectations of others, and control beliefs about one’s own capacity to perform the behaviour. Applied to information seeking, this framework helps explain why a patient might type symptoms into a search engine late at night despite knowing that clinicians discourage it. If the patient believes that searching will bring relief from uncertainty, senses that family members expect them to be proactive, and feels confident in their ability to navigate the web, the intention to search online becomes powerful, regardless of the quality of what they find.

The health belief model adds another layer by focusing on perceptions of threat and benefit. A patient who perceives their cancer as severe and themselves as highly susceptible to progression may be more motivated to seek information aggressively, but that same heightened perception of threat can make dramatic, unverified claims about miracle cures or hidden causes feel plausible. Perceived barriers and self-efficacy, two further constructs of the model, determine whether patients verify what they read or accept it at face value. The interview study suggests that many participants possessed low self-efficacy when it came to evaluating sources, and this deficit became a critical vulnerability.

One of the most consequential findings is that participants relied on superficial methods to search for and evaluate online cancer information, largely to reduce cognitive effort. This behaviour has a rational core. Information search is fundamentally a problem-solving task involving inference and decision-making, and these are precisely the cognitive processes that cancer and its treatments can impair. Chemotherapy-related cognitive changes, often described by patients as difficulty concentrating or remembering, compound the challenge of parsing dense, technical, and sometimes contradictory web content. Under such conditions, shortcuts become attractive: judging a website by its professional appearance, trusting the first result a search engine returns, or accepting information because it appears repeatedly across multiple pages.

These heuristics, while efficient, are unreliable proxies for accuracy. Search engine rankings reflect popularity and optimisation rather than medical validity, and polished design is no guarantee of sound science. The study’s participants were not careless; they were conserving limited mental energy during an exhausting period of their lives. Recognising this distinction matters for anyone designing interventions, because simply urging patients to be more careful ignores the cognitive realities that make carefulness difficult. Practical tools that lower the effort required for evaluation, such as checklists that prompt a few key questions about a source, may succeed where exhortations to vigilance fail.

Equally revealing is the finding that peer experiences were regarded as a trustworthy source of cancer information. This trust is not irrational. Fellow patients offer lived experience, emotional resonance, and practical advice that clinical materials often lack. Hearing that another person tolerated a treatment regimen or managed a side effect can provide hope and a sense of community that no pamphlet can replicate. The difficulty arises when anecdotal experience is generalised into medical truth. A single patient’s response to an unproven remedy says nothing about its efficacy or safety for others, yet within online communities such stories circulate with persuasive force, particularly when they align with what an anxious reader hopes to hear.

The consequences of misinformation documented in the study extended beyond confusion. Participants reported impacts on both psychological and physical health outcomes. Psychologically, exposure to false or alarming claims fuelled anxiety, eroded hope, and sometimes created conflict between what patients read and what their clinicians told them. Physically, misinformation could lead to delayed treatment decisions, abandonment of prescribed therapies, or adoption of unverified interventions with real risks. These outcomes echo broader findings in the literature: systematic reviews of social media health information quality have identified cancer as one of the topics generating the most quality concerns, and reviews of misinformation prevalence report moderate rates of false content for noncommunicable diseases including cancer.

Against these risks, participants described mitigation strategies centred on trustworthy healthcare communication. Some verified online findings by bringing them to their physicians or nurses; others defaulted to information sources recommended by their care teams. These strategies transformed the clinical encounter into a verification checkpoint, a role that many clinicians already perform informally. The study suggests that this function could be made explicit and systematic. Directing patients to well-known national and international cancer information repositories, and introducing simple evaluation checklists during consultations, would give patients reliable starting points and reduce their dependence on whatever a general search engine surfaces first.

Yet the study also uncovered significant barriers to this kind of open dialogue. Fear of confronting physicians and reluctance to interfere with the consultation process prevented many participants from raising what they had read online. This hesitancy is understandable in contexts where medical authority carries substantial cultural weight and consultation time is limited. Patients may worry that questioning a doctor’s guidance with internet-sourced material will appear disrespectful, or that doing so will consume time needed for pressing clinical matters. The result is a silent gap: misinformation circulates unchallenged in patients’ lives while clinicians remain unaware of it, losing opportunities to correct false beliefs before they influence decisions.

Closing this gap requires deliberate effort on both sides. Clinicians can normalise the conversation by asking patients what they have read online, framing the question as routine rather than accusatory. Health systems can train staff to respond to online findings with curiosity rather than dismissal, since a dismissive reaction may push patients toward secrecy and further reliance on unreliable sources. Patients and caregivers, for their part, benefit from explicit permission and encouragement to bring questions arising from internet searches into their appointments. The study’s participants themselves recommended guidance on searching and evaluating credible information, indicating appetite for exactly this kind of support.

The unmet information needs documented in the study sit within a larger pattern. Integrative reviews of supportive care needs have found that cancer patients and caregivers are frequently dissatisfied with existing options for acquiring information, a finding consistent with international research on unmet information needs across cancer populations. Digital health tools have been proposed as a complement to conventional care precisely to address gaps such as coping support and cancer education, and surveys have identified information and education as the most needed digital health function for this group. The internet’s appeal is amplified for stigmatised conditions, where barriers to traditional information sources make anonymous online searching especially attractive.

The scale of the underlying challenge is considerable. Global cancer incidence is projected to reach 27.5 million new cases by 2040, with deaths rising to 16.3 million, which means the population of information-seeking patients and caregivers will grow substantially in the coming decades. A recent systematic review of information-seeking behaviour among cancer patients identified twenty quantitative studies but only four qualitative ones since 2002, and none of the qualitative work had applied a behavioural theory. The present study fills that methodological gap, and its theoretical grounding offers a template for future research seeking to understand not just what patients do online but why.

For caregivers, the findings carry particular weight. Family members often conduct searches on behalf of patients, filter information before sharing it, and shoulder the emotional labour of translating frightening content into reassurance. Because caregivers were interviewed separately in this study, their perspectives emerge distinctly, underscoring that safeguarding against misinformation is a family-level concern rather than an individual one. Interventions that equip caregivers with evaluation skills may therefore yield benefits that ripple outward to the patients they support.

Ultimately, the study reframes susceptibility to misinformation not as a failure of intelligence or diligence but as a predictable consequence of cognitive strain, emotional urgency, and unmet informational needs converging on a digital environment where credible and false content appear side by side. Solutions that acknowledge this reality, by lowering the effort of verification, strengthening the clinical relationship as a trusted channel, and providing authoritative repositories as default destinations, offer a realistic path forward. As digital health continues to expand its role in cancer care, ensuring that patients and caregivers can navigate it safely becomes not an optional enhancement but a core component of supportive care itself.

Subject of Research: Susceptibility of cancer patients and caregivers to online cancer misinformation

Article Title: Susceptibility of cancer patients and caregivers to online cancer misinformation: a qualitative interview study

Article References: Mohamed, H., Salsberg, J., Alanzi, T., Mohamed, M., & Kelly, D. (2026). Susceptibility of cancer patients and caregivers to online cancer misinformation: a qualitative interview study. Supportive Care in Cancer, 34(10), Article 987. https://doi.org/10.1007/s00520-026-11236-2

Image Credits: AI Generated

DOI: 10.1007/s00520-026-11236-2

Keywords: cancer, misinformation, caregivers, digital health literacy, health belief model, theory of planned behaviour, information-seeking, health communication, oncology, qualitative research, social media, patient safety