B. PHC and Immunization Sector Domains
This part is specific to PHC and immunization. It classifies approaches by the health-system and service-delivery domains they help researchers and implementers investigate. A framework often sits in several domains, with one principal domain.
Domain 1. Health System Governance, Policy and Leadership
Central implementation questionHow do governance arrangements, policies, leadership, institutions and accountability structures influence implementation?
| Subdomain | Relevant theories, models and frameworks |
|---|---|
| Health system governance | WHO Health Systems Framework · Health Systems Governance Framework |
| Policy implementation | Policy Triangle Framework · Policy Implementation Frameworks |
| Institutional arrangements | Institutional Theory · Institutional Analysis and Development Framework |
| Leadership and organisational change | Transformational Leadership Theory · Organizational Readiness for Implementing Change |
| Decentralisation and intergovernmental relationships | Multilevel Governance Frameworks · Institutional Theory |
| Accountability and stewardship | Accountability Frameworks · Principal-Agent Theory |
| Organisational culture and climate | Organizational Culture Theory · Organizational Climate Frameworks |
Application Examples
- Understanding differences in immunization programme performance across states.
- Examining how states and LGAs turn national policies into implementation.
- Understanding the influence of political leadership on PHC implementation.
- Investigating how accountability arrangements affect programme execution.
- Examining the effects of decentralisation on implementation consistency.
Domain 2. PHC Service Delivery, Organisation and Integration
Central implementation questionHow are interventions organised, integrated and delivered within routine PHC systems?
| Subdomain | Relevant theories, models and frameworks |
|---|---|
| Service integration | WHO Framework on Integrated People-Centred Health Services · service integration frameworks |
| Continuity and coordination of care | Chronic Care Model · Continuity of Care Frameworks |
| Clinical and professional practices | Normalization Process Theory · TDF |
| Routine service delivery | CFIR · EPIS |
| Missed opportunities for vaccination | TDF · CFIR · NPT |
| Quality of care | Donabedian's Structure-Process-Outcome Model · Model for Improvement |
| Organisation of PHC services | Primary Health Care Performance Initiative Framework · WHO Operational Framework for Primary Health Care |
Application Examples
- Integrating immunization into antenatal, postnatal, nutrition and sick-child services.
- Reducing missed opportunities for vaccination.
- Improving routine immunization session organisation.
- Strengthening referral and follow-up systems.
- Institutionalising integrated service delivery models.
Domain 3. Health Workforce and Provider Behaviour
Central implementation questionWhat influences the capacity, motivation, behaviour and performance of health workers responsible for implementing PHC and immunization interventions?
| Subdomain | Relevant theories, models and frameworks |
|---|---|
| Health worker behaviour | TDF · COM-B · Behaviour Change Wheel |
| Knowledge and competencies | Social Cognitive Theory · Self-Efficacy Theory |
| Motivation and performance | Self-Determination Theory · Expectancy Theory |
| Organisational readiness | ORIC · Organizational Readiness for Change Theory |
| Professional practices | NPT · Theory of Planned Behaviour |
| Teamwork and collaboration | Relational Coordination Theory · Team Effectiveness Frameworks |
| Supervision and leadership | Transformational Leadership Theory · Supportive Supervision Frameworks |
| Workload and work environment | Job Demands-Resources Model · SEIPS |
Application Examples
- Improving health worker adherence to vaccination schedules.
- Strengthening interpersonal communication with caregivers.
- Improving health worker motivation and accountability.
- Understanding workload-related barriers to immunization.
- Improving supportive supervision and team performance.
Domain 4. Health Financing, Infrastructure and Commodity Systems
Central implementation questionHow do resources, financing arrangements, infrastructure and commodity systems influence the implementation and delivery of PHC and immunization services?
| Subdomain | Relevant theories, models and frameworks |
|---|---|
| Health financing | Health Financing Frameworks · Resource Dependence Theory |
| Resource allocation | Resource Dependence Theory · Principal-Agent Theory |
| Infrastructure and service readiness | WHO Service Availability and Readiness Assessment (SARA) |
| Vaccine supply chain | WHO Effective Vaccine Management (EVM) Framework · Supply Chain Management Frameworks |
| Cold chain and logistics | Vaccine Supply Chain Frameworks · Systems Thinking |
| Resource mobilisation | Resource Dependence Theory |
| Operational resilience | Resilience Engineering · Health System Resilience Frameworks |
| Financial accountability | Public Financial Management Frameworks |
Application Examples
- Understanding how funding delays affect routine immunization implementation.
- Assessing how vaccine stock-outs influence service delivery.
- Understanding the relationship between infrastructure and service readiness.
- Investigating the effects of logistics and cold-chain constraints.
- Examining how state-level resource allocation influences PHC implementation.
Classification caveat: SARA, EVM and public financial management frameworks are primarily operational assessment or health-system management approaches. They are valuable for implementation research. Do not present them as implementation science theories in their own right.
Domain 5. Health Information, Evidence Use and Programme Learning
Central implementation questionHow are information, research evidence and programme-generated data translated into decisions, implementation improvements and organisational learning?
| Subdomain | Relevant theories, models and frameworks |
|---|---|
| Evidence-to-practice translation | Knowledge-to-Action Framework · PARIHS · i-PARIHS |
| Data use and decision-making | Information-to-Action Frameworks · Data Demand and Information Use Frameworks |
| Organisational learning | Organizational Learning Theory · Learning Health System Frameworks |
| Continuous quality improvement | Model for Improvement · PDSA cycles |
| Knowledge management | Knowledge Management Frameworks · Communities of Practice |
| Digital health implementation | NASSS Framework · CFIR |
| Information system adoption | Technology Acceptance Model · Unified Theory of Acceptance and Use of Technology (UTAUT) |
| Implementation monitoring | RE-AIM · Proctor's Implementation Outcomes Framework |
Application Examples
- Improving the use of DHIS2 immunization data for local decision-making.
- Strengthening routine performance review meetings.
- Supporting evidence-informed district planning.
- Integrating digital decision-support tools into immunization management.
- Strengthening feedback and learning loops.
Domain 6. Community Engagement, Demand and Health-Seeking Behaviour
Central implementation questionHow do individuals, households, communities and social structures influence access to, acceptance of and use of PHC and immunization services?
| Subdomain | Relevant theories, models and frameworks |
|---|---|
| Caregiver behaviour | Health Belief Model · COM-B · Theory of Planned Behaviour |
| Vaccine acceptance | 3Cs and 5Cs models of vaccine hesitancy · Social Ecological Model |
| Community engagement | Community Engagement Frameworks · Collective Impact Framework |
| Social norms | Social Norms Theory · Social Network Theory |
| Trust and relationships | Social Capital Theory · Trust Frameworks |
| Health service utilisation | Andersen's Behavioural Model of Health Services Use |
| Community participation | Community Participation Frameworks · Empowerment Theory |
| Communication and behaviour change | Social Cognitive Theory · Behaviour Change Wheel |
| Community-level diffusion | Diffusion of Innovations Theory |
Application Examples
- Understanding reasons for zero-dose status.
- Improving caregiver demand for routine immunization.
- Addressing community mistrust and misinformation.
- Strengthening community participation in PHC planning.
- Improving the relationship between health workers and communities.
Immunization addition: this site also profiles WHO's BeSD framework, built for the drivers of vaccination. See the inventory.
Domain 7. Equity, Access and Implementation in Heterogeneous Settings
Central implementation questionHow do social, geographical, economic, political and contextual differences shape implementation, access and equitable health outcomes?
| Subdomain | Relevant theories, models and frameworks |
|---|---|
| Health equity | Health Equity Implementation Framework · Equity-Based Framework for Implementation Research |
| Social determinants of health | WHO Social Determinants of Health Framework |
| Access to healthcare | Levesque's Patient-Centred Access to Healthcare Framework |
| Geographical accessibility | Geographic Accessibility Frameworks · Three Delays Model (where relevant) |
| Vulnerable and underserved populations | Social Ecological Model · Equity-Oriented Frameworks |
| Gender and social inclusion | Gender Analysis Frameworks · Intersectionality Framework |
| Implementation variation | CFIR · EPIS · Complexity Theory |
| Adaptation to context | FRAME · FRAME-IS · Dynamic Sustainability Framework |
| Health system resilience | Health System Resilience Framework · Resilience Engineering |
Application Examples
- Understanding geographical and social inequalities in immunization coverage.
- Investigating implementation in insecure and hard-to-reach communities.
- Understanding why implementation strategies work differently across states and LGAs.
- Addressing barriers affecting nomadic, migrant and displaced populations.
- Understanding contextual adaptation during large-scale vaccination campaigns.