Why First-Degree Relatives of Colorectal Cancer Patients Say Yes to Colonoscopy but Never Book It

For anyone with a parent, sibling, or child diagnosed with colorectal cancer, the arithmetic of risk is personal and stark. First-degree relatives of patients with colorectal cancer carry a substantially elevated lifetime risk of developing the disease themselves, and clinical guidelines across the world single them out for earlier and more intensive colonoscopy screening. Yet a striking gap persists between what these relatives intend and what they actually do. A new qualitative study from researchers at The Nethersole School of Nursing at The Chinese University of Hong Kong, published in BMC Health Services Research, dissects that gap with unusual precision, mapping exactly where the journey from intention to action stalls — and the findings suggest that the barriers before and after the decision point are fundamentally different in kind.

The research team, led by Bei Dong and corresponding author Carmen Wing Han Chan, set out to answer a deceptively simple question: among Chinese first-degree relatives of colorectal cancer patients, what shapes the formation of colonoscopy screening intention, and what determines whether that intention ever becomes a booked appointment? To explore this, the investigators conducted a qualitative descriptive study guided by the theory of planned behaviour, a widely used psychological framework that models human action as the product of attitudes toward the behaviour, perceived social pressure, and perceived control over performing it. Between May and June 2025, the team carried out semistructured interviews, conducted either face to face or by video call, with participants recruited from one specialised cancer hospital and two comprehensive hospitals in China.

The methodological design reflects a deliberate effort to capture the full spectrum of experience. Using maximum variation sampling, the researchers deliberately selected thirty-two first-degree relatives differing in gender, age, education level, occupation, place of residence, and — critically — their actual colonoscopy screening behaviour. This heterogeneity matters because it guards against the common pitfall of qualitative studies that interview only the willing or the accessible. The interviews were then subjected to content analysis, with the team attending to established criteria of rigour: credibility, transferability, dependability, and confirmability. Ethics approval was secured from the Ethics Committee of the Chinese University of Hong Kong, Soochow University, and Shandong Cancer Hospital, and written informed consent was obtained from every participant in accordance with the Declaration of Helsinki.

What emerged from the analysis was a two-stage architecture of decision-making. The researchers identified three categories of factors influencing whether an intention to undergo colonoscopy screening forms in the first place: perceived colorectal cancer risk, perceived health value of colonoscopy, and advice from others. In the language of the theory of planned behaviour, these map onto the attitude dimension — how a person evaluates the screening itself — and the subjective norm dimension, the perceived social expectation from family, friends, and clinicians. The study concludes that these attitude- and norm-related factors play a decisive role in intention formation, meaning that a relative who does not personally feel at risk, who doubts the value of the procedure, or who receives no encouragement from others may never even reach the point of saying yes.

But intention, the study shows, is only half the battle. Four separate categories of factors govern whether a formed intention translates into action: the priority of colonoscopy, information preparation, psychological preparation, and practical conditions. Priority, the researchers found, is shaped by the perceived urgency of the procedure and by conflict with role responsibilities — the competing demands of work, caregiving, and family obligations that push a discretionary medical appointment down the list. Information preparation involves the knowledge a relative needs about screening procedures themselves, while psychological preparation concerns two of the most feared elements of the colonoscopy experience: bowel preparation and anaesthesia. These intention-to-action factors, the analysis indicates, align with the perceived behavioural control dimension of the theoretical framework — the sense that one can actually carry the behaviour out.

The practical conditions category deserves particular scrutiny because it exposes barriers that no amount of personal motivation can overcome. The study identifies personal financial capacity, accessibility to caregiving support, and organisational support as the concrete enablers — or obstacles — standing between a willing relative and a completed colonoscopy. A person may genuinely want to undergo the procedure, as the article’s evocative title suggests with its trailing ellipsis, yet find the cost prohibitive, lack someone to accompany them or care for dependants during the recovery period, or face services that are simply inaccessible or inconveniently organised. These are structural problems, and the authors argue that structural support should be further optimised to improve the accessibility and convenience of colonoscopy screening services.

The theoretical payoff of the study lies in its stratification of the behavioural pathway. Because attitude- and norm-related factors dominate intention formation while control-related factors dominate the transition to action, the authors propose that interventions can be stratified according to whether first-degree relatives have already formed an intention to undergo colonoscopy screening. For those who have not, efforts should concentrate on risk perception, the perceived health value of the procedure, and social advice — essentially, on changing minds. For those who have formed an intention but remain stuck, the levers are different: information about procedures, reassurance about bowel preparation and anaesthesia, help with scheduling around role responsibilities, and practical support with finances, caregiving, and organisational logistics. A one-size-fits-all campaign, the findings imply, would miss one group or the other.

The clinical context amplifies the significance of these results. Colorectal cancer remains one of the most common malignancies worldwide, and screening by colonoscopy can detect precursor lesions and early-stage disease when treatment is most effective. First-degree relatives of patients occupy a uniquely high-risk tier, which is why interventions targeting both intention formation and action implementation are expected to further increase colonoscopy uptake in this population. The study’s authors frame their work as directly informing the development of precise and efficient interventions — a goal that matters enormously in health systems where screening resources are finite and where the relatives of newly diagnosed patients represent a captive, identifiable, and highly motivated audience for preventive care.

From a health services research perspective, the study also illustrates the value of qualitative methods in behavioural science. Quantitative surveys can measure how many relatives intend to undergo screening and how many actually do, but they cannot reveal why the numbers diverge. By interviewing thirty-two relatives across different hospitals, ages, and backgrounds, the researchers surfaced the texture of the decision: the anxiety about anaesthesia that never gets voiced in a clinic, the parent who cannot leave a sick family member to attend an appointment, the worker who cannot afford the days off, the relative who has heard conflicting advice about whether the procedure is truly necessary. Content analysis of these accounts converted anecdote into a structured, theory-anchored map of the behavioural terrain.

The broader lesson for screening programmes everywhere — not only in China — is that the phrase I want to undergo colonoscopy, but… contains a complete research agenda in four words. The word want points to attitudes and social norms; the word but points to control, logistics, and fear. The study’s conclusion that stratified interventions should be implemented according to whether relatives have formed an intention offers programme designers a practical decision rule, while its call to optimise structural support reminds policymakers that individual resolve cannot substitute for accessible, affordable, and convenient services. As colonoscopy screening expands to reach the first-degree relatives who need it most, the difference between a good intention and a completed procedure may come down to whether the health system treats the ellipsis as seriously as the affirmation that precedes it.

Subject of Research: Factors influencing colonoscopy screening intention and uptake among first-degree relatives of colorectal cancer patients

Article Title: “I want to undergo colonoscopy, but…”: qualitative study of colonoscopy screening intentions and actions amongst first-degree relatives of patients with colorectal cancer

Article References: “I want to undergo colonoscopy, but…”: qualitative study of colonoscopy screening intentions and actions amongst first-degree relatives of patients with colorectal cancer. (n.d.). https://doi.org/10.1186/s12913-026-15603-x

Image Credits: AI Generated

DOI: 10.1186/s12913-026-15603-x

Keywords: colorectal cancer, colonoscopy, first-degree relatives, cancer screening, theory of planned behaviour, qualitative study, health services research, intention-action gap, bowel preparation, anaesthesia, screening barriers, China