Perceptions of the use of biomarkers for Alzheimer's disease diagnosis: A systematic review and synthesis of the qualitative literature.

Biomarker investigations are increasingly used in the diagnostic assessment of Alzheimer's disease (AD), yet stakeholder perceptions and implementation factors remain underexplored. No systematic qualitative synthesis exists on these views. This systematic review aimed to synthesize the qualitative literature on perceptions of diagnostic AD biomarker investigations in both clinical and research settings among individuals with cognitive impairment, caregivers, and health-care professionals (HCPs) and to identify barriers and enablers to their practical implementation. A systematic review searched four databases up to May 2025 for English-language qualitative studies on stakeholder (HCPs, caregivers, patients) perspectives. A meta-ethnographic approach synthesized findings, with barriers/enablers classified using the theoretical domains framework (TDF). From 4319 records, 26 studies were included, yielding five key concepts: stakeholder expectations, test result significance, shared decision-making, diagnostic certainty, and test delivery systems. Barriers included lack of understanding (knowledge) and emotional burden (emotion). Enablers involved supporting decision making (memory, attention, decision processes) and beliefs about testing benefits (beliefs about consequences), though risks were equally noted. Barriers to AD biomarker use involve multiple TDF domains, with contrasting stakeholder viewpoints. Improving knowledge of biomarkers and addressing perceived benefits and risks can guide interventions, promoting more effective test use.