[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-study-detail:100659557":3},{"organization":4,"outcomesModule":7,"designInfo":28,"detailedDescription":37,"studyPopulation":31,"armGroups":38,"interventions":49,"overallOfficials":31,"centralContacts":55,"locations":31,"responsibleParty":61,"collaborators":31,"id":65,"slug":66,"hasResults":67,"nctId":68,"briefTitle":69,"officialTitle":70,"acronym":31,"eligibilityCriteria":71,"healthyVolunteers":72,"sex":73,"minAge":74,"maxAge":31,"enrollmentInfo":75,"targetDuration":31,"studyType":78,"phases":79,"briefSummary":81,"conditions":82,"keywords":84,"overallStatus":91,"whyStopped":31,"lastUpdateSubmitDate":92,"lastUpdatePostDateStruct":93,"startDateStruct":96,"completionDateStruct":97,"leadSponsor":99,"locationsCount":31},{"fullName":5,"class":6},"Fudan University","OTHER",{"primaryOutcomes":8,"secondaryOutcomes":13,"otherOutcomes":18},[9],{"measure":10,"description":11,"timeFrame":12},"Influenza Vaccination Uptake","Whether participants get vaccinated against influenza, measured by official vaccination records.","1 month and 3 months after the intervention",[14],{"measure":15,"description":16,"timeFrame":17},"Timing of Influenza Vaccination","Number of days from the intervention date to receipt of influenza vaccination, measured by official vaccination records.","Within 3 months after the intervention",[19,22,25],{"measure":20,"description":21,"timeFrame":12},"Spouse Influenza Vaccination Uptake","Whether the participant's spouse gets vaccinated against influenza, measured by official vaccination records.",{"measure":23,"description":24,"timeFrame":17},"Timing of Spouse Influenza Vaccination","Number of days from the participant's intervention date to spouse's influenza vaccination, measured by official vaccination records.",{"measure":26,"description":27,"timeFrame":17},"Incremental Cost-Effectiveness Ratio (ICER)","Cost per additional vaccinated person and cost per additional quality-adjusted life year (QALY) gained, calculated from both health-system and societal perspectives using micro-costing data. QALYs projected over annual horizon.",{"allocation":29,"interventionModel":30,"interventionModelDescription":31,"primaryPurpose":32,"observationalModel":31,"timePerspective":31,"maskingInfo":33},"RANDOMIZED","PARALLEL",null,"HEALTH_SERVICES_RESEARCH",{"masking":34,"maskingDescription":31,"whoMasked":35},"SINGLE",[36],"OUTCOMES_ASSESSOR","Influenza vaccination is the most effective measure for preventing influenza. However, the influenza vaccination rate in China is extremely low, with older adults, a high-risk group for influenza, having a vaccination rate of only about 4%. Beginning in 2026, China provides free influenza vaccination for adults aged 65 years and older in rural areas, and allows the personal accounts of employees' basic medical insurance to be used to pay for influenza vaccination for the account holders and their family members, thereby removing the economic barrier to vaccination. Under these payment policies, how to design effective behavioral intervention strategies to increase the vaccination rate has become an important issue.\n\nThis study proposes to conduct three independent, parallel cluster randomized controlled trials to implement a family-physician influenza vaccination nudge intervention among adults aged 55 years and older, and to evaluate the effect of the intervention on improving the influenza vaccination rate among older adults under three distinct payment policies. The three sub-trials are conducted under the free vaccination policy for adults aged 65 years and older in rural areas, the self-paid vaccination policy for adults aged 55-64 years in rural areas, and the partially insurance-covered vaccination policy for adults aged 55 years and older in urban areas, respectively. A health economic evaluation will be conducted concurrently, together with a feasibility evaluation based on semi-structured interviews, so as to empower family physicians to promote vaccination among older populations.\n\nSample sizes are calculated independently for the three sub-trials, based on the primary outcome measure (influenza vaccination uptake) and the main analysis method (comparison of rates between two groups). For the rural sub-trial (free-vaccine policy), taking 10% vaccination rate as the control-group baseline and assuming the nudge intervention raises the rate to 18% (an 8-percentage-point absolute increase), with α = 0.05 (two-sided) and ICC = 0.02, an average of 20 participants per cluster and 54 clusters (family physicians) are required to achieve the power of 90%, resulting in a total sample of 1,080 adults aged 65 years and older. For the rural sub-trial (out-of-pocket policy), taking 4% vaccination rate as the control-group baseline and assuming the intervention raises the rate to 8% (a 4-percentage-point increase, attenuated by economic factors), with the same α and ICC, and an average of 43 participants per cluster and 54 clusters (family physicians) are required to achieve the power of 85%, resulting in a total sample of 2,322 adults aged 55-64 years. For the urban sub-trial (out-of-pocket\u002Finsurance policy), taking 5% vaccination rate as the control-group baseline and assuming the intervention raises the rate to 10% (a 5-percentage-point increase, attenuated by economic factors), with the same α and ICC, and an average of 44 participants per cluster and 42 clusters (family physicians) are required to achieve the power of 85%, resulting in a total sample of 1,848 adults aged 55 years and older.\n\nA cluster randomized controlled design will be employed across three representative regions in China. Taking the level of economic development into account, three provinces are selected from the eastern, central, and western regions, and in each province, 3-4 community health service centers (CHCs) are selected in urban and rural areas respectively. In total, 9-12 urban\u002Frural CHCs are recruited, yielding approximately 42 urban and 54 rural family physician clusters. Older adults will be recruited during the primary care visits at the participating CHCs, where all eligible patients meeting inclusion criteria are invited to participate and provide informed consent.\n\nRandomization is performed independently for each sub-trial, with the family physician as the cluster unit. The randomization sequence will be generated in advance by an independent statistician using a computer-generated random number method. Owing to the nature of the intervention, both family physicians and participants are aware of group assignment, and blinding cannot be fully implemented; however, local coordinators, outcome assessors, data managers, and statistical analysts are blinded to group allocation.\n\nThe intervention group receives a three-component nudge: (1) an endowment-framing educational pamphlet and verbal recommendation for influenza vaccination by the family physician; (2) on-site default appointment (opt-out) for vaccination; and (3) a telephone reminder at two weeks for those not yet vaccinated. The control group maintains the existing routine service model, with only standard influenza vaccination health education provided during routine encounters.\n\nThe intention-to-treat (ITT) approach is used as the primary analysis strategy. Influenza vaccination status at 1 month and 3 months is analyzed using generalized estimating equations (GEE) with the family physician as the clustering unit and the community health service center as a fixed effect, adjusting for prespecified covariates (region, sex, age, marital status, type of medical insurance in the urban sub-trial, and prior influenza vaccination history). Adjusted relative risk and absolute risk difference with 95% confidence intervals are reported. Time-to-vaccination is evaluated using Kaplan-Meier curves and Cox proportional hazards models with robust standard errors. Prespecified subgroup analyses assess heterogeneity of intervention effects. A per-protocol analysis serves as a sensitivity analysis. A health economic evaluation (cost-effectiveness with ICER calculation) and a feasibility evaluation via semi-structured interviews with family physicians and older adults are conducted alongside the trial.",[39,45],{"label":40,"type":41,"description":42,"interventionNames":43},"Family Physician Nudge Group","EXPERIMENTAL","In addition to routine health education, participants in this arm receive a multicomponent nudge delivered by their family physician during a routine primary care encounter. The nudge consists of: (1) an endowment-framing educational pamphlet and verbal recommendation for influenza vaccination by the family physician; (2) on-site assistance with scheduling a vaccination appointment as the default (opt-out) option; and (3) a telephone reminder two weeks after the encounter for those who have not yet completed vaccination. The intervention is delivered during the 2026-2027 influenza vaccination season.",[44],"Behavioral: Family Physician Influenza Vaccination Nudge",{"label":46,"type":47,"description":48,"interventionNames":31},"Routine Care Group","NO_INTERVENTION","Participants assigned to the control arm receive routine care - the family physician sees them per standard clinical procedures and provides only routine health education on influenza vaccination, without the deliberate use of the nudge intervention components (no structured recommendation, no default appointment, no two-week telephone reminder).",[50],{"type":51,"name":52,"description":53,"armGroupLabels":54,"otherNames":31},"BEHAVIORAL","Family Physician Influenza Vaccination Nudge","A family-physician-delivered behavioral nudge combines provider recommendation by an endowment-framing educational pamphlet, default appointment scheduling, and a follow-up reminder, which is designed to increase influenza vaccination uptake among older adults. Grounded in behavioral science theories of vaccination decision-making and nudging, the intervention leverages the high credibility of primary-care family physicians among older adults and reduces the behavioral frictions associated with seeking vaccination.",[40],[56],{"name":57,"role":58,"phone":59,"phoneExt":31,"email":60},"Zhiyuan Hou, PhD","CONTACT","86+21 54231112","zyhou@fudan.edu.cn",{"type":62,"investigatorFullName":63,"investigatorTitle":64,"investigatorAffiliation":5,"oldNameTitle":31,"oldOrganization":31},"PRINCIPAL_INVESTIGATOR","Zhiyuan Hou","Associate Professor","100659557","family-physician-nudges-for-influenza-vaccination-among-older-adults-100659557",false,"NCT07864597","Family Physician Nudges for Influenza Vaccination Among Older Adults","Family Physician Nudges for Influenza Vaccination Among Older Adults: Cluster Randomized Trials","Inclusion Criteria:\n\n* Age ≥ 55 years.\n* Not vaccinated against influenza in the current flu season.\n* No contraindications to influenza vaccination.\n* Willing and able to provide informed consent and participate in the study.\n\nExclusion Criteria:\n\n* Age under 55 years.\n* Has already received influenza vaccination in the current flu season.\n* Has a known contraindication to influenza vaccination.\n* Unable to comply with study procedures.\n* Unwilling or unable to provide informed consent.",true,"ALL","55 Years",{"count":76,"type":77},5250,"ESTIMATED","INTERVENTIONAL",[80],"NA","The goal of this clinical trial is to learn if a family-physician nudge intervention works to improve influenza vaccination among adults aged 55 years and older in China. Three independent, parallel cluster randomized controlled trials will be conducted under three distinct vaccine payment policies, i.e. free vaccination for those older than 65 years and self-paid vaccination for those \\\u003C65 years in rural areas, and partially insurance-covered vaccination in urban areas.\n\nThe main questions it aims to answer are:\n\n1. Does the family-physician nudge intervention increase influenza vaccination uptake among older adults? How does the effectiveness of the nudge intervention vary under different payment policies？\n2. Is the family-physician nudge intervention cost-effective, acceptable, feasible, and potentially sustainable in primary care settings? Researchers will compare an intervention group receiving a family-physician nudge with a control group receiving routine care to see if the nudge is effective at increasing influenza vaccination among older adults.\n\nParticipants will:\n\n1. Be recruited at community health service centers and cluster-randomized by their family physicians into one of two groups.\n2. Receive either a physician nudge (provider recommendation by an endowment-framing educational pamphlet + default appointment + a follow-up reminder) or routine health education.\n3. Have their influenza vaccination status verified through the immunization information system at the end of the trial.",[83],"Influenza Vaccination",[85,86,87,88,89,90],"influenza vaccination","nudge","family physician","clinical trial","older adults","behavioral science","NOT_YET_RECRUITING","2026-10-02",{"date":94,"type":95},"2026-10-08","ACTUAL",{"date":94,"type":77},{"date":98,"type":77},"2027-06",{"name":5,"class":6}]