Box 3.

Barriers and facilitators identified in the data, linked to the TICD checklist

TICD domain headings with relevant determinants of practice	Barriers to implementation identified in the data mapped on to the TICD checklist	Facilitators of implementation identified in the data mapped on to the TICD checklist
Guideline factors
Quality of evidence Strength of recommendation Accessibility of recommendation Feasibility	Lack of certainty that benefits outweigh harms Perceived lack of easy access to resources at point of care	Accessible evidence-based guidelines
Individual health professional factors
Skills needed to adhere Agreement towards guidelines Emotions Nature of the behaviour/capacity to plan to change	Lack of expertise communicating risk assessment results Lack of consensus on approach to education Reluctance to reduce screening frequency for common cancers/potential fidelity Fear of missing a cancer Lack of time for risk-tailored patient discussions	Professional education: communicating risk assessment results GP expertise with screening programmes/risk factors Perceived benefit of reduced screening frequency where screening tests are invasive
Patient factors
Patient needs Patient beliefs and knowledge Patient behaviour	Patient resistance to screening advice Concern about patient anxiety related to high-risk results Patient response/confusion from changes in screening advice	Professional education — communicating risk assessment results Targeted public messages
Incentives and resources
Continuing education system Assistance for clinicians	Lack of time for education/to become an evidence-based provider	Evidence-based guidelines and risk calculators
Capacity for organisational change
Priority of necessary change	Lack of perceived priority to change practice
Social, political and legal factors
Economic constraints on the health budget	Reluctance for change if cost-effectiveness is the only reason for change	Potentially cost-effective

TICD = Tailored Implementation for Chronic Diseases.