title: A note on the power prior.
abstract: The power prior by Ibrahim and Chen (Statist. Sci. 2000; 15:46-60) is one of several methods to incorporate historical data in the analysis of a clinical trial. The power prior raises the likelihood of the historical data to the power parameter a(0) which quantifies the discounting of the historical data due to heterogeneity between trials. It is shown that the standard method of estimating the power parameter from the historical and current data is inappropriate, and we therefore suggest to use a modified power prior approach or to consider alternative methods instead.
authors.affiliation: Novartis Pharma AG, Biometrics, Basel, Switzerland. beat.neuenschwander@novartis.com
authors.forename: Beat
authors.initials: B
authors.lastname: Neuenschwander
authors.forename: Michael
authors.initials: M
authors.lastname: Branson
authors.forename: David J
authors.initials: DJ
authors.lastname: Spiegelhalter
mesh_terms: D002986:Clinical Trials as Topic / Q000379:methods; D003627:Data Interpretation, Statistical; D006801:Humans