Priority populations’ experiences of isolation, quarantine and distancing for COVID-19: protocol for a longitudinal cohort study (Optimise Study)
Authors: Pedrana Alisa , Bowring Anna , Heath Katherine , Thomas Alexander J , Wilkinson Anna , Fletcher-Lartey Stephanie , Saich Freya , Munari Stephanie , Oliver Jane , Merner Bronwen , Altermatt Aimee , Nguyen Thi , Nguyen Long , Young Kathryn , Kerr Phoebe , Osborne Deborah , Kwong Edwin Jit Leung , Corona Martha Vazquez , Ke Tianhui , Zhang Yanqin , Eisa Limya , Al-Qassas Adil , Malith Deng , Davis Angela , Gibbs Lisa , Block Karen , Horyniak Danielle , Wallace Jack , Power Robert , Vadasz Danny , Ryan Rebecca , Shearer Freya , Homer Caroline , Collie Alex , Meagher Niamh , Danchin Margaret , Kaufman Jessica , Wang Peng , Hassani Ali , Sadewo Giovanni Radhitio Putra , Robins Garry , Gallagher Colin , Matous Petr , Roden Bopha , Karkavandi Maedeh Aboutalebi , Coutinho James , Broccatelli Chiara , Koskinen Johan , Curtis Stephanie , Doyle Joseph S , Geard Nicholas , Hill Sophie , Coelho Alison , Scott Nick , Lusher Dean , Stoové Mark A , Gibney Katherine B , Hellard Margaret 
Published: January 2024

IntroductionLongitudinal studies can provide timely and accurate information to evaluate and inform COVID-19 control and mitigation strategies and future pandemic preparedness. The Optimise Study is a multidisciplinary research platform established in the Australian state of Victoria in September 2020 to collect epidemiological, social, psychological and behavioural data from priority populations. It aims to understand changing public attitudes, behaviours and experiences of COVID-19 and inform epidemic modelling and support responsive government policy.Methods and analysisThis protocol paper describes the data collection procedures for the Optimise Study, an ongoing longitudinal cohort of ~1000 Victorian adults and their social networks. Participants are recruited using snowball sampling with a set of seeds and two waves of snowball recruitment. Seeds are purposively selected from priority groups, including recent COVID-19 cases and close contacts and people at heightened risk of infection and/or adverse outcomes of COVID-19 infection and/or public health measures. Participants complete a schedule of monthly quantitative surveys and daily diaries for up to 24 months, plus additional surveys annually for up to 48 months. Cohort participants are recruited for qualitative interviews at key time points to enable in-depth exploration of people’s lived experiences. Separately, community representatives are invited to participate in community engagement groups, which review and interpret research findings to inform policy and practice recommendations.Ethics and disseminationThe Optimise longitudinal cohort and qualitative interviews are approved by the Alfred Hospital Human Research Ethics Committee (# 333/20). The Optimise Study CEG is approved by the La Trobe University Human Ethics Committee (# HEC20532). All participants provide informed verbal consent to enter the cohort, with additional consent provided prior to any of the sub studies. Study findings will be disseminated through public website (https://optimisecovid.com.au/study-findings/) and through peer-reviewed publications.Trial registration numberNCT05323799.