The COVID-19 pandemic has forced the implementation of physical distancing and self-isolation strategies worldwide. However, these measures have significant potential to increase social isolation and loneliness. Among older people, loneliness has increased from 40% to 70% during COVID-19. Previous research indicates loneliness is strongly associated with increased mortality. Thus, strategies to mitigate the unintended consequences of social isolation and loneliness are urgently needed. Following the Obesity-Related Behavioural Intervention Trials model for complex behavioural interventions, we describe a protocol for a three-arm randomised clinical trial to reduce social isolation and loneliness.

A multicentre, outcome assessor blinded, three-arm randomised controlled trial comparing 12 weeks of: (1) the HOspitals WoRking in Unity (‘HOW R U?’) weekly volunteer-peer support telephone intervention; (2) ‘HOW R U?’ deliver using a video-conferencing solution and (3) a standard care group. The study will follow Consolidated Standard of Reporting Trials guidelines.

We will recruit 24–26 volunteers who will receive a previously tested half day lay-training session that emphasises a strength-based approach and safety procedures. We will recruit 141 participants ≥70 years of age discharged from two participating emergency departments or referred from hospital family medicine, geriatric or geriatric psychiatry clinics. Eligible participants will have probable baseline loneliness (score ≥2 on the de Jong six-item loneliness scale). We will measure change in loneliness, social isolation (Lubben social network scale), mood (Geriatric Depression Score) and quality of life (EQ-5D-5L) at 12–14 weeks postintervention initiation and again at 24–26 weeks.

Approval has been granted by the participating research ethics boards. Participants randomised to standard care will be offered their choice of telephone or video-conferencing interventions after 12 weeks. Results will be disseminated through journal publications, conference presentations, social media and through the International Federation of Emergency Medicine.

NCT05228782.