title: Inter-provider comparison of patient-reported outcomes: developing an adjustment to account for differences in patient case mix.
abstract: This paper describes the development of a methodology for the case-mix adjustment of patient-reported outcome measures (PROMs) data permitting the comparison of outcomes between providers on a like-for-like basis. Statistical models that take account of provider-specific effects form the basis of the proposed case-mix adjustment methodology. Indirect standardisation provides a transparent means of case mix adjusting the PROMs data, which are updated on a monthly basis. Recently published PROMs data for patients undergoing unilateral knee replacement are used to estimate empirical models and to demonstrate the application of the proposed case-mix adjustment methodology in practice. The results are illustrative and are used to highlight a number of theoretical and empirical issues that warrant further exploration. For example, because of differences between PROMs instruments, case-mix adjustment methodologies may require instrument-specific approaches. A number of key assumptions are made in estimating the empirical models, which could be open to challenge. The covariates of post-operative health status could be expanded, and alternative econometric methods could be employed.
authors.affiliation: Department of Health, London, UK.
authors.forename: David
authors.initials: D
authors.lastname: Nuttall
authors.forename: David
authors.initials: D
authors.lastname: Parkin
authors.forename: Nancy
authors.initials: N
authors.lastname: Devlin
mesh_terms: D017677:Age Distribution; D000368:Aged; D015897:Comorbidity; D003953:Diagnosis-Related Groups; D017558:Elective Surgical Procedures / Q000706:statistics & numerical data*; D005006:Ethnicity; D005260:Female; D006304:Health Status; D006801:Humans; D007343:Insurance Carriers; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D017059:Models, Econometric; D017063:Outcome Assessment, Health Care; D020379:Risk Adjustment / Q000379:methods*; D017678:Sex Distribution; D006113:United Kingdom
keywords: PROMs, case-mix adjustment; patient-reported outcomes