Older People's Preventive Care Utilization

Objectives: To empower older people's decision making for taking the recommended vaccines including seasonal influenza vaccines, pneumococcal vaccines, and COVID-19 vaccine (if it is recommended annually).

Hypotheses to be tested: The interventions designed using Mental Models Approach and Patient Activation Approach will promote older people's confidence in knowledge and skills regarding vaccination decisions, perceived self-efficacy in self-management of health, positive emotional engagement with vaccination decisions and a positive future time perspective which will subsequently promote their uptake of the recommended vaccines.

Design and subjects: This will be a two-arm randomized control trial. Subjects will be community-dwelling older people aged 70 years or above.

Instruments: A questionnaire will be used to collect baseline data before the interventions and follow-up data 1 months and 4 months, respectively, after the end of interventions.

Interventions: Interventions included one booklet to communicate information about preventive care by bridging expert knowledge and older people's existing mental models, and six patient activation sections conducted over telephone. One patient activation section will be delivered per week by trained medical students.

Main outcome measures: Main outcomes will be participants' uptake of the three recommended vaccines assessed at 1 month and 4 months after the end of interventions.

Data analysis and expected results: Generalized estimating equation logistic regression will be used to assess the intervention effects. The investigators expect that the interventions can promote at least 20% increase in uptake of any one of the three recommended vaccines in the intervention group compared with the control group.