Older adult loneliness is associated with depression, disability and higher mortality rates. As a public health concern, it contributes to increased medical and nursing care costs. Several intervention studies have been conducted to reduce loneliness; however, no universally effective method has been established. We hypothesise that if older adults use their physical abilities to perform petit volunteering, their feelings of loneliness would likely be reduced. This trial aims to investigate the benefits of using petit volunteers for loneliness alleviation (PetitVOLA) application as a sustainable programme to prevent loneliness through the creation of an Ikigai-based volunteer system.

We intend to conduct a randomised controlled trial with a 3-month intervention period to verify the effectiveness of the PetitVOLA programme (sample size, 126 participants; power, 0.8; significance level, 0.05). The primary outcome is loneliness, which we will measure using the UCLA Loneliness Scale (V.3). Secondary outcomes include social isolation (assessed via multicomponent objective criteria), life satisfaction, physical function (gait speed and grip strength), cognitive function, psychological status and lifestyle, each assessed with validated instruments (eg, Mini-Mental State Examination, Geriatric Depression Scale-15 and the Active Mobility Index). The main analysis uses an intention-to-treat approach, while a full analysis set and a per-protocol set are included for sub-analyses.

The trial was approved by the Human Research Ethics Committee of the National Center for Geriatrics and Gerontology, Japan (approval No. 1794). The results of this trial will be disseminated through peer-reviewed journals, conference presentations and reports to the participating community.

UMIN000056649.