Table 2.

Overview of Barriers and Facilitators for Implementation of the PHQ-4

Theme	Construct CFIR	Barriers and Facilitators
1. Quality of the intervention	Design quality and packaging (+, −)	• Characteristics and content PHQ-4 (+, −)•Characteristics and content manual (+)
	Relative advantage (+)	•Lack of depression and anxiety questionnaire (+)•Limited guidelines discussing mental health (+)•Added value for follow-up care (+)
	Evidence strength and quality (+, −)	•Increasing attention for mental health (+)•Tool to discuss depression and anxiety (+)•Outcome represents mental health (problems) (+, −)
2. Applicability for clients of LVS organizations	Patient needs and resources (+, −)Adaptability (+, −)	•Suitability for all clients of LVS organizations (−)•Standard administration (+, −)•Practical challenges administration (−)•Administration modes (+)
3. Attitude and needs clients	Patients’ needs and resources (+, −)	•Defensive, practical, and closed attitude (−)•Willingness to discuss mental health (+, −)•Preferences for health care providers that administer PHQ-4 differ (−)•Preferred moment of administration differs (−)•Clients’ focus on practical support for VI (−)•Influence health care provider on openness clients (+, −)
	Relative advantage (+, −)	•Importance of implementation PHQ-4 (+)•Preferences for current practice (−)
4. Attitude health care providers	Self-efficacy (+, −)	•Need for various competencies (−)•Need for knowledge (−)•Confidence in discussing mental health (+, −)
	Knowledge and beliefs (+, −)	•Implementation is important and necessary (+)•Reluctance to use PHQ-4 (−)
	Available resources (+)	•Availability of suitable professions that can administer the PHQ-4 within LVS organizations (+)
5. Support within low-vision organizations	External policy and incentives (−)	•No clear mutual perspective on procedures for intakes and mental health care (−)•No clear mutual perspective on the PHQ-4 (−)
	Tension for change (+)	•(Increased) current attention for mental health (+)•Current limited guidelines (+)
6. Embedding in current practice	Compatibility (+, −)	•Applicability existing procedures (+)•Intensive and exploratory nature of intake (−)•Lack of follow-up procedures (−)
	Patients’ needs and resources (+, −)	•Variety of follow-up care (−)•Possibility for periodical assessments (+)•Preferred interval periodical assessments differ (−)•Record results in medical file (+)
	Available resources (+, −)	•Limited costs (+)•High workload (−)•Increased burden clients and health care providers (−)•Integration in digital medical files (+)
	Structural characteristics (−)	•Differences between locations (−)•Organizational changes (−)

(−), barrier; (+), facilitator; (+, −), barrier and facilitator.