A community-based, multicenter study is currently underway in South Korea to evaluate the effectiveness of Widely Integrated Services in Home (WISH) for homebound older adults. The study, titled "Widely Integrated Services in Home (WISH) for homebound older adults: a study protocol for a pragmatic randomized encouragement design trial," aims to determine if integrated home-based care can improve outcomes such as reducing hospitalizations and increasing community survival days.
The trial employs a prospective, two-arm, parallel-group, outcome assessor-blinded, pragmatic, randomized encouragement design with a 12-month follow-up period. Participants are recruited from five urban areas, including Northeast Seoul, West Seoul, Daejeon, Wonju, and Paju, through community screening and referrals from the National Long-Term Care Insurance (NLTCI) system and Home-Based Care Services (HCBS).
Eligibility and Randomization
To be eligible, participants must be older adults (age ≥ 65 years) living at home, certified as NLTCI Grade 1 to 5 (registration score ≥ 45), experiencing functional deterioration (Clinical Frailty Scale [CFS] ≥ 4), and have multimorbidity with unmet healthcare needs. Exclusion criteria include an expected survival time of less than 1 month, preference for admission to a long-term care (LTC) facility, or participation in other home-based medical services.
Participants are randomly assigned to either the Home-Based Primary Care (HBPC) group or the usual care group at a 1:1 allocation ratio. Random assignment is performed after screening but before the initial home visit, with the randomized sequence generated by an independent third party. The study utilizes a randomized encouragement design, where participants in the HBPC group are encouraged to engage in longitudinal home visits according to the WISH intervention protocol, while those in the usual care group receive no specific information about the HBPC program.
WISH Intervention Protocol
The WISH intervention protocol was developed to minimize heterogeneity in HBPC practices among centers. It includes a series of case conferences, resulting in a list of the 20 most encountered clinical problems, eight evidence-based intervention components, and practical strategies. Each patient in the HBPC group is assigned to an interprofessional care team comprising a physician, nurse, and social worker. A designated case manager conducts home visits at least once a month to provide healthcare and family counseling services. The care team performs a Comprehensive Geriatric Assessment (CGA) during the first three home visits to generate clinical and psychosocial problem lists and establish individualized care plans, reassessed every six months.
The six key differences between the intervention and usual care groups are:
- Pilot Project Registration: Invitation to register as a participant in the Home-Based Medical Center Demonstration project.
- Interventionists: Program offered by an interprofessional care team.
- Total number and duration of home visits: At least 12 home visits during the intervention period.
- Individualized care planning using the WISH Matrix: CGA to identify major issues to reduce symptoms and caregiver burden.
- Trained workers provide healthcare and/or social services for 12 months according to the individualized care plan.
- Specially designed program to prevent institutionalization (optional): Interventions such as interagency care team meetings, transitional care programs, and after-hour telephone counseling.
Outcome Measures and Data Analysis
The primary outcomes of the trial are community survival days, potentially avoidable hospitalizations, and dying at home. Secondary outcomes include emergency department visit rate, unplanned readmissions, use of outpatient services, annual health and LTC spending, reductions in symptom burden and caregiver burden, patient satisfaction, healthcare service provider acceptance, and changes in functional status and clinical condition.
Data analysis will be conducted using both modified intention-to-treat (ITT) and complier average causal effect (CACE) analytic methods. Kaplan–Meier methods and Weibull regression will be used to compare community survival days between the two groups. CACE analytic methods will address potential attrition bias, estimating the average impact of the intervention on those who comply with their treatment assignment.
Ethical Considerations
The study protocol was approved by the Institutional Review Board (IRB) of Chung-Ang University. Two written informed consent forms are obtained from all participants prior to the baseline assessment. All researchers and HBPC team members completed the research certification for Korean Good Clinical Practice and a training workshop regarding the trial procedures.
