title: Prognostic models based on literature and individual patient data in logistic regression analysis.
abstract: Prognostic models can be developed with multiple regression analysis of a data set containing individual patient data. Often this data set is relatively small, while previously published studies present results for larger numbers of patients. We describe a method to combine univariable regression results from the medical literature with univariable and multivariable results from the data set containing individual patient data. This 'adaptation method' exploits the generally strong correlation between univariable and multivariable regression coefficients. The method is illustrated with several logistic regression models to predict 30-day mortality in patients with acute myocardial infarction. The regression coefficients showed considerably less variability when estimated with the adaptation method, compared to standard maximum likelihood estimates. Also, model performance, as distinguished in calibration and discrimination, improved clearly when compared to models including shrunk or penalized estimates. We conclude that prognostic models may benefit substantially from explicit incorporation of literature data.
authors.affiliation: Center for Clinical Decision Sciences, Department of Public Health, Erasmus University, P.O. Box 1738, 3000 DR Rotterdam, The Netherlands. steyerberg@mgz.fgg.eur.nl
authors.forename: E W
authors.initials: EW
authors.lastname: Steyerberg
authors.forename: M J
authors.initials: MJ
authors.lastname: Eijkemans
authors.forename: J C
authors.initials: JC
authors.lastname: Van Houwelingen
authors.forename: K L
authors.initials: KL
authors.lastname: Lee
authors.forename: J D
authors.initials: JD
authors.lastname: Habbema
mesh_terms: D000367:Age Factors; D000368:Aged; D048909:Diabetes Complications; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000150:complications; D006973:Hypertension / Q000150:complications; D016013:Likelihood Functions; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality*; D011379:Prognosis; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects; D013997:Time Factors