Impact of a community-based asynchronous review clinic on appointment attendance delays across an eye hospital network in London, UK: an interrupted time series analysis

OBJECTIVE: To assess the impact of opening a large community-based asynchronous review ophthalmic clinic on attendance delays among patients with stable chronic eye disease attending a London teaching eye hospital network. DESIGN: Interrupted time-series analysis of routine electronic health records of appointment attendances. SETTING: A large eye hospital network with facilities across London, UK, between June 2018 and April 2023. PARTICIPANTS: We analysed 69 257 attendances from 39 357 patients, with glaucoma and medical retina accounting for 62% (n=42 982) and 38% (n=26 275) of visits, respectively. Patients over 65 made up 54% (n=37 824) of attendances, while 53% (n=37 014) were from the more deprived half of the population, and 51% (n=35 048) were males. INTERVENTION: An asynchronous review clinic opened in a shopping centre in London, in autumn 2021, following the COVID-19 lockdown in spring 2020. MAIN OUTCOME MEASURES: Average attendance delays (days), calculated as the difference between follow-up attendance date and the latest clinically appropriate date determined at the preceding attendance. RESULTS: Pre-COVID-19, attendance delays for chronic eye disease monitoring were increasing by 0.9 days per week (95% CI, 0.8 to 0.9) on average, worsening to 2.0 days per week (95% CI, 2.0 to 2.0) after the first COVID-19 national lockdown, mid-March 2020. Opening the asynchronous review clinic increased appointment capacity, with delays decreasing on average by 8.1 days per week (95% CI, 8.1 to 8.2) shortly after opening. The rate of decrease slowed to 0.3 days per week (95% CI, 0.3 to 0.3) after 5 months. We found no significant differences in average attendance delays by age, gender or level of deprivation. CONCLUSION: The asynchronous review clinic significantly reduced attendance delays across the hospital network, addressing pre-existing backlog for stable chronic eye diseases. The reduction appeared to be maintained after the initial backlog had been cleared.