This multicenter pilot study evaluates the feasibility, implementation fidelity, and preliminary effects of the GAP-421 (Personalized Care Management) model for chronic pain management in primary care physiotherapy. The GAP model is a time-limited organizational modality that reconfigures schedules, resources, and professional roles during a defined 6-week window to organize care around the individual patient and their trajectory, formalizing coordination work that previously occurred informally.

The study uses a convergent mixed-methods design across three primary care health centers in the Southeast Healthcare District (DASE) of the Community of Madrid, Spain. The quantitative component is a prospective multicenter pre-post case series with 3-month follow-up (n=66 patients, 22 per center). The qualitative component includes semi-structured interviews (n=12) and focus groups (3 groups, n=6 each). Integration occurs through Joint Display, Pillar Integration Process, and a 9-type legitimation framework.

The primary outcome is patient-perceived care coordination measured on a 0-10 numerical scale (PREM). Secondary outcomes span five domains: patient-reported outcomes (EQ-5D-5L, Graded Chronic Pain Scale, pain intensity), professional outcomes (coordination burden, role clarity), system sustainability (avoidable re-consultations, emergency department use), implementation fidelity, and feasibility indicators.

Results will generate feasibility parameters, intraclass correlation coefficient estimates, and process indicators essential for designing definitive cluster-randomized trials testing organizational interventions in primary care physiotherapy.

BACKGROUND:

Primary care faces a structural mismatch between the growing complexity of patients with chronic pain and an organizational architecture designed for acute episodes and independent schedules. International guidelines (NICE NG193, WHO 2023) recommend multimodal approaches with a function-centered focus consistent with physiotherapy competencies, yet interprofessional coordination relies on unrecognized informal work, generating hidden workload, care fragmentation, and inappropriate transfer of organizational responsibilities to patients.

The Burden of Treatment Theory and Cumulative Complexity Model explain that when organizational burden exceeds patient capacity, the result is organizational design failure rather than patient non-adherence. Recent evidence from the Community of Madrid (Izquierdo Enriquez et al., 2026) revealed a striking paradox: 72.8% of primary care physicians consider education and exercise superior to pharmacological treatment, yet 62.8% still consider opioids effective for chronic non-cancer pain, illustrating the gap between declarative adherence to biopsychosocial approaches and pharmacologically-dominated practice.

THE GAP MODEL:

The GAP (Personalized Care Management) model proposes a time-limited functional modality that reconfigures the interaction between schedules, resources, and professionals so that care is organized around a specific person and their trajectory. It operates through four features: temporality (activates and deactivates), reconfiguration (reorganizes existing resources without creating parallel structures), person-centeredness (designed from the patient trajectory), and organizational legitimacy (converts invisible coordination into explicit, recorded, and evaluable work).

INTERVENTION:

The GAP-421 model operates on Service 421 (chronic pain) of the Primary Care Service Portfolio of the Community of Madrid through a 6-week window structured in four phases:

• Day 0 (Activation): Lead physiotherapist identifies 2 or more organizational mismatch signals. Documented in standardized GAP Activation Form.
• Week 1 (Characterization): Concentrated comprehensive assessment. Protected non-face-to-face coordination time. Classification of functional status, burden-capacity profile, shared clinical message.
• Weeks 2-4 (Intervention): Therapeutic education, graded exercise, pharmacological adjustment if indicated. Aligned messages across professionals. Exercise plan with adherence monitoring.
• Weeks 4-6 (Closure): Semi-annual plan with milestones, de-escalation criteria, return to standard circuit. Follow-up plan, reactivation signals, patient feedback.

Key organizational changes include: physiotherapist schedule incorporating comprehensive GAP assessment slot (45-60 min), weekly protected interprofessional coordination time (15-20 min), and closure session (30-40 min); family physician allocating 5-15 min/week for coordination and message alignment; nursing conducting socio-familial assessment when indicated.

THEORETICAL FRAMEWORK:

The study is grounded in Normalization Process Theory (NPT), Burden of Treatment Theory, and the GAP conceptual model.

SAMPLE SIZE:

n=66 patients (22 per center) calculated with design effect correction (DEFF=2.05, ICC=0.05, effect size d=0.60, 20% attrition).

ANALYSIS:

Quantitative: Wilcoxon/paired t-tests, exploratory multilevel mixed models (patients nested within centers), Cohen's d with 95% CI. R v4.3.

Qualitative: Reflexive thematic analysis with inductive-deductive coding using NPT constructs. Atlas.ti v24.

Integration: Joint Display convergence matrix, Pillar Integration Process, Onwuegbuzie and Johnson 9-type legitimation framework. Quality: MMAT 2018, GRAMMS checklist.

Inclusion Criteria:

• Adults aged 18 years or older
• Enrolled in Service 421 of the Madrid Primary Care Service Portfolio (chronic non-cancer pain of at least 3 months duration)
• Pain intensity NRS of 4 or higher in the last 2 weeks OR functional limitation score of 2 or higher (Annex 54, SERMAS Service Portfolio)
• Ability to understand and sign informed consent
• Ability to complete study questionnaires in Spanish

Exclusion Criteria:

• Active cancer pain
• Documented moderate-to-severe cognitive disorder (ICD-10 diagnosis or registered functional assessment)
• Decompensated psychiatric disorder that, in the clinical judgment of the physiotherapist and/or family physician, interferes with study participation
• Immediate clinical emergency at enrollment
• Simultaneous participation in another clinical trial or organizational intervention study
• Anticipated inability to complete 3-month follow-up (planned relocation, imminent institutionalization)
• Explicit refusal to participate

Anonymized individual participant data will be made available upon reasonable request to the corresponding author after publication of primary results. Data will be deposited in an open-access repository.

Beginning 6 months after publication of primary results. Available for 5 years.

Researchers who provide a methodologically sound proposal. Proposals should be directed to raul.ferrer@salud.madrid.org. To gain access, data requestors will need to sign a data access agreement.

Open-label organizational intervention. Partial blinding applies only to the assessment of system sustainability outcomes (Domain C): electronic health record review for avoidable re-consultations is conducted by two independent evaluators blinded to intervention timing (Cohen's kappa minimum 0.60 required for inter-rater agreement).