Impact of the COVID-19 pandemic on opioid agonist treatment in Ireland: Protocol for an interrupted time series analysis

While opioid agonist treatment (OAT) is the most effective for dependence, it heavily dependent on regular face-to-face healthcare delivery placing both clients and providers at risk of COVID-19. Following emergence COVID-19, policies were rapidly changed in Ireland, with introduction national contingency guidelines by HSE National Social Inclusion Office, beginning March 2020 to ensure rapid uninterrupted access OAT while balancing efforts mitigate COVID-19 risk. This study aims assess impact guidelines, quality care delivered Ireland. An interrupted time series analysis will be conducted using anonymised aggregated level data obtained from Central Treatment List (CTL), register people receiving OAT, administered Drug Centre Board behalf HSE. Separate segmented regressions estimate following outcomes: (1) number patients treatment; (2) starting OAT; (3) average waiting (4) list; (5) dropping out treatment. The period divided into pre-(March 2019 February 2020) post- intervention (April 2021) segments. Immediate (change level) longer-term impacts slope) changes provision each outcomes investigated. Regression coefficients (β) 95% confidence intervals (CIs) reported.