Strengthening the Evidence Base of Cancer Symptom Awareness Campaigns: A Conceptual Framework

Abstract

Background: Cancer control strategies in different countries increasingly encompass public health education campaigns that aim to promote earlier presentation and diagnosis of cancer by raising awareness of possible cancer symptoms. However, the theoretical understanding that underpins these complex early diagnosis interventions remains underdeveloped. Aim: To propose a theoretical framework to guide the design, implementation, and evaluation of cancer symptom awareness campaigns and motivate further relevant research. Methods: Informed by Wilson and Junger's principles of early disease detection for screening (1968) and existing conceptual frameworks for early diagnosis of cancer, we considered the logic model underlying cancer symptom awareness campaigns and relevant emerging evidence from disciplines including health psychology, cancer epidemiology, and health services research. Real-world examples across high-/low-income settings were used where possible to illustrate discussions of implications for practice. Results: We identified four major factors that contribute to the logic model of cancer symptom awareness campaigns beyond contextual and practical factors. Disease burden statistics (cancer site-specific incidence, survival, mortality) could be used to gauge relative need for raising awareness. This should be triangulated with symptom epidemiology (including existing levels of awareness, symptom prevalence, the associated predictive value for cancer, symptom-specific diagnostic timeliness, and whether the symptom is a sign of early stage disease) to motivate selection of individual symptoms in a campaign. Psychosocial factors (such as cancer fatalism or fear and health literacy) and their interaction with symptom awareness should also be considered as they affect symptom appraisal. Further, an understanding and awareness of system factors (availability and access to healthcare, investigation processes, and clinical capacity) will be important for assessing campaign feasibility and knock-on effects in the health system. Based on the above, campaigns should ideally target symptoms that are strongly predictive of early stage (treatable) cancer for which there is low awareness in the target population, and are associated with long intervals to help-seeking. Campaign impact should be amplified by targeting psychosocial barriers to prompt presentation. Additionally, campaigns should be accompanied by downstream capacity planning for potential cancer investigation and subsequent treatment. Conclusion: The proposed framework considers the logic model of cancer symptom awareness campaigns, acknowledging key factors that should be taken into account beyond contextual factors. This could help identify evidential gaps in early diagnosis research, and improve campaign design and evaluation.