Objectives To explore how pre-existing conditions affect the diagnostic process for potential cancer in primary care patients. Design Qualitative interview study using thematic analysis underpinned by a critical realist approach. Setting Primary care practices recruited through four Clinical Research Networks and UK health charities across England. Participants Interviews were conducted with 75 patients with one or more pre-existing conditions (anxiety/depression, diabetes, obesity, chronic obstructive pulmonary disease, Parkinson’s disease or multiple long-term conditions (four or more)) and 28 primary care professionals (general practitioners and nurses). Results The study identified legitimacy as a central theme influencing patient trajectories in the health system while trying to receive a diagnosis for symptoms with which they presented to primary care. Patients engaged in self-triage to determine whether symptoms were ‘legitimate’ enough to seek care. Subsequent triaging steps (by receptionists, nurses and online systems) acted as gatekeepers, with decisions influenced by effectiveness of describing the symptom and subjective impressions. During consultations, clinicians relied on a mix of symptom narrative clarity, medical history and objective ‘metrics’ (eg, blood results, family history) to determine legitimacy for further investigations. Pre-existing conditions could either lower the threshold for referrals or obscure potential cancer symptoms. The stigma associated with mental health diagnoses often undermined perceived legitimacy and contributed to delays. Conclusions Legitimacy is continuously negotiated throughout the diagnostic pathway. It is shaped by social, moral and biomedical judgements. To promote early cancer diagnosis for patients with pre-existing conditions, clinicians must make legitimacy assessments explicit, reduce stigma especially around mental health and standardise triage processes.
Valasaki et al. (2025) studied this question.