The National Health System of England National Collaboration for Integrated Care and Support states that for health, care and support to be integrated, it must be person-centred, coordinated, and tailored to the needs and preferences of the individual, their career and family.1 It means moving away from episodic care to a more holistic approach to health, care and institutional support, that puts the needs and experience of people at the centre of how services are organised and delivered. A similar vision is provided by The Nuffield Trust when describing the aim of integrated care as the effort to join up the health and care services required by individuals, to deliver care that meets their personal needs in an efficient way.2 Similar orientation is observed in New South Wales Health in Australia where involves the provision of seamless, effective, and efficient care that reflects the whole of a person's health needs.3 A similar perspective is offered by the World Health Organization (WHO), which describes integrated care as an approach aimed at strengthening person-centred health systems through the comprehensive delivery of quality services across the life course, tailored to the multidimensional needs of both populations and individuals, and coordinated across settings and levels of care by multidisciplinary teams.4

There is a general notion that integrated care (i.e., access to family- and community-oriented primary health care supported by a responsive hospital system) leads to better health outcomes.5 Beyond rhetoric, there is a general notion that this approach to integrated care leads to better health outcomes through care defragmentation. Indeed, in health systems with a strong reliance on regulated provision and primary care gatekeeping as Italy, Portugal, Spain or Sweden, potentially avoidable admissions for chronic conditions, those likely benefitting from integrated care, tend to be lower in international comparison; however, it is also true that countries as United Kingdom, with the same institutional design, do not follow the same pattern; and, on the contrary, systems as the Dutch, a system reliant on market mechanisms in service provision and ample capacity for patients to choose insurance, consistently exhibit very low rates of avoidable admissions.6

From a procedural perspective, integrated care is used to describe a connected set of clinical, organizational, and policy changes aimed at improving service efficiency, patient experience, and health outcomes. Hughes et al. identified four perspectives on integrated care.7 First, the concept of person-centeredness as the space to be recognised and heard, where patients take appropriate control of their own care. Second, strategies to integrated care that include change management (i.e., proactive, planned, preventive, self-managed), multidisciplinary working (i.e., health and social care collaboration, roles shifting), linking organizations (i.e., seamless technological coordination, multisite cooperation, overall care pathway accountability), and overall system approaches (i.e., universal primary care with gatekeeping roles, hospital centric, long-term care oriented). Third, models that range from linkages (referrals between services) through coordination (smoothing transitions between services) to full integration (into a single organizational body); and fourth, theoretical and critical analysis that comprises strategies to unify care and organizations, shaped by economic, political, and social contexts and subject to the governance and power relations.

The concept of integrated care is framed within a context of social justice, emphasizing that if equity is not prioritized, the integrated care model could perpetuate existing inequities instead of addressing them.8 Furthermore, recent studies highlight that even well-established integrated care models may fail to achieve equitable outcomes unless they are intentionally designed with equity in mind9. Whereas equity is recognized as a fundamental aspect of integrated care, an in-depth exploration of equity is beyond the intended scope and space of the current manuscript.

In this manuscript, we review relevant literature to shed light on whether integrated care can improve health outputs and outcomes. We use the term integrated care as a synonym for “coordinated care”, “transmural care”, “interprofessional care”, “seamless care”, “comprehensive care”, and “patient-centred care”. The paper aims to identify lessons for fostering integrated care in the Spanish National Health System.

This scoping review aimed to map the literature on integrated care policy instruments from a primary care perspective, classify them by conceptual domains, and identify available evidence on their effects on health outcomes.

A conceptual map (Fig. 1) was developed, covering domains such as coordination mechanisms, incentive structures, resource distribution, professional capacities, communication channels, and governance, with political will and patient-related factors treated as cross-cutting drivers. The framework was refined inductively as new dimensions emerged during screening (Table S1 in Supplementary Material describes the dimensions of the conceptual map).

Figure 1.

Conceptual map for integrated care.

Searches were conducted in PubMed in April–May 2025 using the term “integrated care” combined with predefined analytical dimensions. Reference lists of included reviews were also screened. Reviews were eligible if they addressed integrated care instruments relevant to primary care or across care settings; disease-specific reviews were excluded. The process included a structured search and examination of academic, peer-reviewed publications. In addition, the review was informed by prior related work and the study team's expertise in integrated care. Three reviewers (AF, DV, DGA) screened titles and abstracts. Coauthors were assigned the topics for analysis; after literature revision, overlaps in scope, unclarity, and gaps in the retrieved information were jointly discussed. When information on a topic was missed, additional literature was searched. Given inconsistent reporting of impacts on health outcomes, relevance was determined by each review's conceptual contribution to understanding these relationships. Additional attention was paid to the depth with which political determinants were linked to integrated care implementation.

Data were charted according to the conceptual map and synthesised narratively. In line with scoping review methodology, no formal quality appraisal or meta-analysis was undertaken. 36 full-text papers were assessed for eligibility, while 18 papers were included in the review.

This scoping review included 18 reviews (10 scoping reviews, 5 systematic reviews and 3 meta-analyses) for a total of 1037 individual studies (see Table S2 in Supplementary Material). The search yielded in addition one comparative secondary analysis, one realistic synthesis report, two policy papers, semistructured interviews and qualitative case-studies that, along with relevant papers within the reviews, were analysed apart to complement the analyses. No reviews were found addressing political will.

The most prevalent approach to study integrated care was narrative and partial. Evidence on the potential impact of integrated care on outputs and health outcomes was found to be scarce, and those studies aiming to show the effect suffered from methodological limitations and rarely sought to be generalisable.

This review of reviews, where integrated care was analysed from the perspective of primary care, sought to elicit evidence on the effect of different policy instruments on integrated care, as well as, on the association between integrated care and care process and health outcomes improvements. With the caveat of these results being based on limited evidence, generally built on studies with methodological flaws and restricted capacity for generalisation, care models seemed to be more effective when addressing integrated care in a comprehensive way, considering patients’ perspectives in usual care, and are funded using bundled episode-based schemes with shared-savings. For the rest of policy instruments (availability of resources, professional knowledge and skills, and communication channels) although it has been described plausible mechanisms towards better integrated care, there is no available evidence, or evidence was found to be weak or showed no association.

When it comes to the impact of integrated care on care processes and health outcomes, irrespective of the policy instruments, evidence is generally inconclusive. The literature revised showed contradictory findings and evidence varied widely. The heterogeneity in the conditions and processes analysed, and the measurements used to assess effectiveness do not allow drawing uniform conclusions.

Some lessons can be drawn out of those specific studies for our health system. The Spanish experience shows that isolated interventions, such as case management or ICT tools, are not sufficient unless embedded in broader, systemic reforms. Effective integration requires coordination across all levels of care, strong primary care leadership, and genuine patient empowerment. Importantly, political and institutional commitment at our multilevel governance framework is essential to move from successful pilots to sustainable, system-wide change.

This study included narrative, scoping, systematic reviews and meta-analyses where integrated care (and its synonyms) and the different policy instruments towards integrated care was the objective. Although the first intention was carrying a review of systematic review with meta-analyses, validating the hypothesis that integrated care was better than non-integrated care in many endpoints —process care outputs and health outcomes— the majority of evidence does not come from quasi-experimental designs. We tried to mitigate this fact, separately analysing those quasi-experiments carried out in the Spanish SNS.

Despite the extensive literature assessment, some knowledge gaps persist and will require further assessments; notably, the limited evidence found on the effect of some integrated care instruments (e.g., resources distribution, roles-shifting, application of eHealth and mHealth tools, inclusion of the patients’ perspective), the lack of quasi-experimental research at system-level, the absence of comparative research at meaningful levels of decision (i.e., comparison of integrated care implementation across health care areas and autonomous communities), or the lack of efficiency analysis from the societal perspective.

The reviewed evidence highlights that political will is a necessary condition for advancing integrated care, but not sufficient to produce the required cultural and organisational change, and therefore improve care process outputs or health outcomes. Indeed, Mur-Veeman et al.44 showed that although active government policies can foster integrated care, alignment with values (between professionals, but also between institutions) and sufficient resources are also needed. Their comparative analysis across European countries indicated that dynamics between actors (shaped by power relations, roles, and expectations) are conditioned by the broader architecture of the health system, other public administration sectors, and their governance. This last idea also developed in Martens et al.45 referred to the dispersion of authority across federal and regional levels that prevented sustainable care integration and hindered measurable improvements in coordination or efficiency. In turn, Borgermans et al.46 argued that integrated care requires not only high-level commitment but also disruptive innovation (deep structural reforms), adaptative models based on person-centred care and intersectoral collaboration.

Nicholson et al.47 identified as key elements for the governance of care integration: joint planning, integrated information and technology, change management, shared clinical priorities, incentives, population focus, data-driven quality improvement, continuous professional development, patient and community engagement, and innovation. Successful integration would in any case require political will, investment, risk-management and adaptive paths. Along the same lines, leadership is crucial for a successful integration, particularly between health and social care systems.48 Leaders must navigate complex environments and foster trust and collaboration, balancing inspiration with practical knowledge. Shared leadership is often more effective, with leaders prioritizing community needs while promoting innovation and learning despite current pressures. Despite this narrative, users’ and patients’ perspective, and policymakers’ views regarding the impact of integration and leadership benefits is currently lacking.

When it comes to the specific case of Spain, a recent Organisation for Economic Co-operation and Development and WHO report analysing the purchasing arrangements to strengthen the quality of chronic care in three Spanish Autonomous Communities assessed different policy instruments used to ensure integrated care.49 The successful implementation of purchasing instruments requires wide consensus and commitment from the main stakeholders, including health professionals and health systems managers. Strong regulatory instruments facilitate implementation, but do not guarantee sustainable change towards integrated care. The development of fit-for-purpose information systems is key to foster improvements in the quality of care. The lack of publicly available data and lack of independent evaluations impede full understanding of the programmes’ impact.

This literature review has highlighted the need for strengthening coordination between the health and social sectors. However, the knowledge gap on the actual impact of this coordination on care outputs and health outcomes is still scarce. The development of the 2025-2027 Action Plan of Primary and Community Health may well be an opportunity for the development of that intersectoral space, potentially evaluable, while filling in the lack of evidence.50

On a final note, the Spanish examples in this review highlight the need for strengthened governance in the evaluation of integrated care interventions within our health system. Advancing towards high-quality, people-centred care calls for shared research frameworks, appropriate methodologies and outcome measures, and structured mechanisms for reporting and learning from implementation. A more consistent and evidence-informed evaluation approach will be key to ensuring that integrated care efforts are effective, scalable, and responsive to the needs of patients, caregivers, and professionals alike.

The data underlying this study are available from the lead author upon reasonable request.

Salvador Peiró.

All the authors contributed equally in the design, execution and final approval of this manuscript.

Network for Research on Chronicity, Primary Care, and Health Promotion (RICAPPS), Spain Grant numbers RD24/0005/0005; RD24/0005/0014; RD24/0005/0019; RD24/0005/0020.

None.