ENRICH Study: A Mixed-methods Feasibility Study of a Nurse-led Model of Care for Social Frailty in Philippine Primary Care

Background Social frailty refers to reduced social resources, diminished social roles, and decreased participation in meaningful social activities. Among older adults it is associated with loneliness, depression, disability, poorer quality of life, hospitalization, and mortality. In the Philippines, social vulnerability in later life is shaped by structural barriers, including cost, transport, fragmented services, digital exclusion, and disaster-related disruption, and by growing strain on family and community support. Routine primary care does not yet systematically screen for, classify, or respond to social frailty. Few interventions explicitly target social frailty as a multidomain condition, particularly in Asian and low- and middle-income settings, and a brief, conceptually grounded, culturally relevant screening tool for routine primary care use is lacking. Nurses in public primary care already provide assessment, health education, care coordination, and community linkage, and may be well placed to identify socially frail older adults and coordinate a response if supported by a feasible, structured model of care.

Aim and objectives The Evidence-based Nurse-led Risk-informed Intervention for Community-based Healthy Ageing (ENRICH) Study aims to assess the feasibility, acceptability, fidelity, and implementation readiness of a culturally adapted, nurse-led Social Frailty Care Bundle (SFCB) for socially pre-frail and socially frail community-dwelling older adults in one primary health center in Manila City, Philippines, in preparation for a future definitive trial. The objectives are to (1) co-design and refine a contextually appropriate nurse-led SFCB for public primary care; (2) assess the feasibility and implementation of nurse-led SFCB delivery, including nurse recruitment, training completion, competency, retention, acceptability, appropriateness, fidelity, reach, and participant adherence and engagement; (3) evaluate the feasibility of study procedures, including screening, enrollment, retention, follow-up completion, data completeness, and documentation of usual care; (4) explore the experiences of older adults, nurses, carers, and stakeholders, including barriers, facilitators, and refinement needs; and (5) generate feasibility and implementation parameters, including progression criteria and candidate outcome measures, for a future multi-site or cluster randomized controlled trial.

Design and frameworks This is a single-arm, single-site, mixed-methods feasibility and pilot implementation study informed by the Lancaster and Thabane (2019) guidelines for non-randomized pilot and feasibility studies, adapted from the Consolidated Standards of Reporting Trials (CONSORT) extension for pilot and feasibility trials. There is no randomization, comparator group, or control site. A single site allows close monitoring of intervention delivery, participant safety, data governance, and workflow fit before any multi-site trial. Four phases are conducted sequentially, with findings from each informing the next. The intervention framework applies the PRECEDE-PROCEED model (Predisposing, Reinforcing, and Enabling Constructs in Educational Diagnosis and Evaluation - Policy, Regulatory, and Organizational Constructs in Educational and Environmental Development; Green et al., 2022) to identify predisposing, reinforcing, and enabling determinants of social frailty and to link assessment to tailored action. The feasibility evaluation is organized by the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework, and the Consolidated Framework for Implementation Research (CFIR) is used to explain contextual and process factors across the innovation, outer setting, inner setting, individuals, and implementation process.

Setting and participants The study will be conducted in one public primary health center in Manila City, selected on the basis of administrative support, availability of nurses involved in older adult care, older adult service volume, feasibility of the ENRICH workflow, and readiness for research. Participants include community-dwelling older adults, registered nurses, family carers, health center administrators, barangay health workers, and representatives of senior citizens' organizations, local government, non-governmental organizations, and faith-based or community services. Each group provides separate informed consent. Nurse participants are registered nurses working at the participating health center who expect to remain at the site during the pilot. Other stakeholders are aged 18 years or older, with relevant knowledge of older adult services, referral systems, or community resources.

Phase 1: Translation and cultural adaptation of the Montayre Social Frailty 10 (MSF-10) The MSF-10 is a 10-item social frailty screening tool developed and validated among community-dwelling older adults in Hong Kong, published as the Social Frailty 10-Item screening tool (SF-10; Montayre et al., 2026). It will be translated into Filipino following Beaton et al. (2000): two independent forward translations (one by a nurse and one by a non-medical translator), synthesis, back-translation by a translator who has not seen the original, and expert review of meaning, cultural relevance, clarity, and equivalence. Because the investigators are members of the MSF-10 development team, the expert panel will include at least one independent reviewer, and all adaptation decisions will be documented. The pre-final Filipino version will be tested in cognitive interviews (think-aloud and probing, about 20 to 30 minutes each) with approximately 15 community-dwelling older adults, purposively sampled for variation in age, sex, education, familiarity with written Filipino, and community background. No psychometric validation is performed in this study; screening cut-offs derived from the Hong Kong validation sample are applied provisionally, and pilot score distributions will inform local threshold calibration.

Phase 2: Participatory co-design of the SFCB Approximately 6 to 12 participants, including older adults, family carers, registered nurses, and community and service stakeholders, will take part in focus groups, participatory workshops, small-group consultations, or one-to-one feedback sessions, in person or online. Co-design will refine the bundle components, care-planning procedures, referral and linkage pathways, follow-up procedures, documentation tools, participant materials, and fidelity monitoring procedures. It will also produce a site-specific referral directory, finalized before recruitment begins.

Phase 3: Nurse training and competency checks Up to 5 registered nurses at the participating health center (total population sampling) will complete self-paced online modules and in-person workshops using simulation, case discussion, skills demonstration, coaching, and reflective debriefing. Content covers social frailty and healthy ageing, the ENRICH workflow, use of the Filipino MSF-10, domain-based assessment, SFCB components, care planning, referral and linkage, sensitive communication, documentation, and fidelity monitoring. Nurses receive an ENRICH manual and complete competency checks led by the investigators before delivering the intervention; nurses who need additional support receive coaching. Recruitment is kept separate from supervisory processes where feasible, and individual training and competency data are not shared with supervisors.

Phase 4: Pilot implementation and qualitative evaluation Older adults will be screened with the Filipino MSF-10 at the health center and during approved community outreach. Those who screen as socially pre-frail or socially frail and meet the eligibility criteria will be invited to enroll. The target of approximately 30 participants is set to estimate feasibility parameters, not to test effectiveness; if eligible older adults exceed the target, stratified purposive sampling may be used to include both pre-frail and frail participants. Enrolled participants receive the SFCB in addition to usual care for 3 months, with data collection at baseline and at 3 months. Usual care at the site, such as routine consultations, chronic disease monitoring, health education, and existing senior citizen services, will be documented before implementation begins. After implementation, approximately 10 to 20 older adults, nurses, carers, and stakeholders will take part in interviews or focus groups on acceptability, feasibility, workflow fit, burden, safety, and refinement needs.

Intervention The SFCB is a structured nurse-led pathway with five workflow steps: (1) social frailty screening with the Filipino MSF-10 within routine primary care; (2) domain diagnosis across four social frailty domains (Bunt et al., 2017): general resources, social resources, social behavior and activity, and self-management abilities; (3) domain-specific action, in which nurses address practical barriers, link participants to family, community, caregiver, and intergenerational supports, co-create meaningful participation plans, and provide brief education, coaching, reminders, or check-ins; (4) follow-up and stepped care, with light-touch contact about every 4 weeks for socially pre-frail or lower-risk participants, structured care plans with proactive monitoring for socially frail participants with modifiable barriers, and escalation to nurse-led case management for persistent or complex needs; and (5) metrics and feedback through structured documentation and fidelity monitoring. Every participant receives at minimum baseline screening and assessment, an individualized care plan, at least one planned follow-up contact, referral or linkage when indicated, and the 3-month follow-up assessment. Components not delivered by the nurse, such as group activities or peer support, are accessed through referral, signposting, or linkage to existing services and are activated only when relevant to the participant's needs, preferences, safety, and available resources. Family members and other third parties are involved only with the participant's permission. All documentation uses structured paper-based ENRICH forms.

Analysis Quantitative analysis is descriptive: frequencies and percentages for categorical variables, and means and standard deviations or medians and interquartile ranges for continuous variables. Feasibility proportions will be reported with 95% confidence intervals and will not be treated as definitive evidence of feasibility or effectiveness. No hypothesis testing or imputation is planned, and missing data will be described by amount, timing, variable, and reason. MSF-10 scores will be summarized descriptively as a candidate clinical outcome; effectiveness is not tested. Fidelity will be assessed with a structured checklist completed after each participant encounter, with an audit of at least 20% of participant records. Qualitative data will be analyzed using framework analysis, with CFIR as the initial deductive coding framework, inductive codes for content outside CFIR, independent double-coding of a subset of transcripts, and an audit trail of coding decisions. Quantitative and qualitative findings will be integrated at interpretation. Progression to a future trial will be judged against pre-specified traffic-light (green, amber, red) criteria for nurse training completion, consent, retention, fidelity, and data completeness, with thresholds given under the outcome measures.

Consent and safety Brief verbal consent is obtained for MSF-10 screening only. Screening data from people who do not enroll are not retained for research; only anonymous aggregate screening counts are kept, and older adults identified as socially pre-frail or frail who do not enroll are still offered signposting or referral. Written informed consent is obtained before any research data collection, using a six-question teach-back to confirm understanding; guardian or legally authorized representative consent is not used. Audio recording is optional and consented separately. A site-specific referral directory and approved procedures cover emotional distress, possible self-harm, suspected abuse or neglect, unmet medical and social welfare needs, food insecurity, transport barriers, and emergencies, and limits to confidentiality are explained during consent. Adverse events, protocol deviations, and data breaches are logged, reviewed by the principal investigator, and reported to the ethics boards as required.

Data protection Participants are assigned unique study identifiers. Identifiable data remain in the Philippines, and only coded or de-identified data are stored in encrypted institutional storage at The Hong Kong Polytechnic University, consistent with the Philippine Data Privacy Act of 2012 (Republic Act 10173). Data are retained for 5 years after study completion or final publication, whichever is later, and then securely destroyed.

Ethics, oversight, and funding The study was approved by The Hong Kong Polytechnic University Institutional Review Board (HSEARS20260525001). Approval from the University of the Philippines Manila Research Ethics Board and permission from the Manila Health Department will be obtained before any participant is enrolled. The investigators are members of the MSF-10 development team; this potential conflict of interest is mitigated through independent review during cultural adaptation, transparent documentation of adaptation decisions, and descriptive reporting of all feasibility outcomes regardless of direction. The study is self-funded.