Using primary care data to understand opioid prescribing, policy impacts and clinical outcomes: A protocol for the OPPICO study

Introduction: Prescription opioid use in Australia has increased over the last 3 decades. The majority of opioids are prescribed and dispensed in primary care, however, there are few studies that are specific to opioid prescribing in this setting. Evidence about the impact of key government policy strategies to optimize opioid prescribing in primary care is limited. The aim of this study is to examine the impact of recent policy changes and clinical guidelines on opioid prescribing in primary care. Methods and analysis: Longitudinal analysis of people prescribed opioid analgesics using Population Level Analysis and Reporting (POLAR) data. POLAR is a primary care dataset comprising 464 primary health care practices in Victoria, Australia. People prescribed opioid analgesics between 2015 and 2020 will be included. The impact of opioid policies and guideline recommendations will be evaluated using interrupted time series models. Group- based trajectory modelling and multivariate regression will be used to identify patterns of opioid cessation and the provision of corresponding non-opioid interventions. Ethics and dissemination: The study has received Monash University Human Research Ethics Committee approval (ID 24139). Permission to access, collate and use POLAR data is granted from Outcome Health as the data custodians. The results of this study will be disseminated through publication in international journals, presented at national and international scientific conferences, and disseminated to consumers, policy makers, primary care providers and primary health networks. Protocol registration details: EU PAS Register (EUPAS43218)