Quantifying Queensland patients with cancer health service usage and costs: study protocol

Introduction: The overall mortality rate for cancer has declined in Australia. However, socioeconomic inequalities exist and the out-of-pocket costs incurred by patients in Australia are high compared with some European countries. There is currently no readily available data set to provide a systematic means of measuring the out-of-pocket costs incurred by patients with cancer within Australia. The primary aim of the project is to quantify the direct out-of-pocket healthcare expenditure of individuals in the state of Queensland, who are diagnosed with cancer. Methods and analysis: This project will build Australia's first model (called CancerCostMod) of out-of-pocket healthcare expenditure of patients with cancer using administrative data from Queensland Cancer Registry, for all individuals diagnosed with any cancer in Queensland between 1 July 2011 and 30 June 2012, linked to their Admitted Patient Data Collection, Emergency Department Information System, Medicare Benefits Schedule and Pharmaceutical Benefits Scheme records from 1 July 2011 to 30 June 2015. No identifiable information will be provided to the authors. The project will use a combination of linear and logistic regression modelling, Cox proportional hazards modelling and machine learning to identify differences in survival, total health system expenditure, total out-of-pocket expenditure and high out-of-pocket cost patients, adjusting for demographic and clinical confounders, and income group, Indigenous status and geographic location. Results will be analysed separately for different types of cancer