title: Parameter Heterogeneity In Breast Cancer Cost Regressions - Evidence From Five European Countries.
abstract: We investigate parameter heterogeneity in breast cancer 1-year cumulative hospital costs across five European countries as part of the EuroHOPE project. The paper aims to explore whether conditional mean effects provide a suitable representation of the national variation in hospital costs. A cohort of patients with a primary diagnosis of invasive breast cancer (ICD-9 codes 174 and ICD-10 C50 codes) is derived using routinely collected individual breast cancer data from Finland, the metropolitan area of Turin (Italy), Norway, Scotland and Sweden. Conditional mean effects are estimated by ordinary least squares for each country, and quantile regressions are used to explore heterogeneity across the conditional quantile distribution. Point estimates based on conditional mean effects provide a good approximation of treatment response for some key demographic and diagnostic specific variables (e.g. age and ICD-10 diagnosis) across the conditional quantile distribution. For many policy variables of interest, however, there is considerable evidence of parameter heterogeneity that is concealed if decisions are based solely on conditional mean results. The use of quantile regression methods reinforce the need to consider beyond an average effect given the greater recognition that breast cancer is a complex disease reflecting patient heterogeneity.
authors.affiliation: Health Economics Research Centre, Nuffield Department of Population Health, University of Oxford, Oxford, UK.
authors.forename: Joel
authors.initials: J
authors.lastname: Smith
authors.affiliation: Centre for Research on Health and Social Care Management, CERGAS, Bocconi University.
authors.forename: Helen
authors.initials: H
authors.lastname: Banks
authors.affiliation: Usher Institute of Population Health Sciences and Informatics, The University of Edinburgh, Edinburgh, UK.
authors.forename: Harry
authors.initials: H
authors.lastname: Campbell
authors.affiliation: Usher Institute of Population Health Sciences and Informatics, The University of Edinburgh, Edinburgh, UK.
authors.forename: Anne
authors.initials: A
authors.lastname: Douglas
authors.affiliation: Lothian Analytical Services, NHS Lothian, Edinburgh, UK.
authors.forename: Eilidh
authors.initials: E
authors.lastname: Fletcher
authors.affiliation: NHS Lothian, Edinburgh, UK.
authors.forename: Alison
authors.initials: A
authors.lastname: McCallum
authors.affiliation: Department of Health Management and Health Economics, Institute of Health and Society, University of Oslo, Oslo, Norway.
authors.forename: Tron Anders
authors.initials: TA
authors.lastname: Moger
authors.affiliation: Centre for Health and Social Economics (CHESS), National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Mikko
authors.initials: M
authors.lastname: Peltola
authors.affiliation: Medical Management Centre, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Sofia
authors.initials: S
authors.lastname: Sveréus
authors.affiliation: Usher Institute of Population Health Sciences and Informatics, The University of Edinburgh, Edinburgh, UK.
authors.forename: Sarah
authors.initials: S
authors.lastname: Wild
authors.affiliation: Usher Institute of Population Health Sciences and Informatics, The University of Edinburgh, Edinburgh, UK.
authors.forename: Linda J
authors.initials: LJ
authors.lastname: Williams
authors.affiliation: Health Research Institute, University of Limerick, Limerick, Ireland.
authors.forename: John
authors.initials: J
authors.lastname: Forbes
mesh_terms: D001943:Breast Neoplasms / Q000191:economics*; D005060:Europe; D005260:Female; D017721:Hospital Costs / Q000706:statistics & numerical data; D006801:Humans; D017059:Models, Econometric; D012044:Regression Analysis
keywords: breast cancer; cost distribution; parameter heterogeneity; quantile regression