title: Development and validation of a prediction model with missing predictor data: a practical approach.
abstract: OBJECTIVE
  To illustrate the sequence of steps needed to develop and validate a clinical prediction model, when missing predictor values have been multiply imputed.
  
  
  METHODS
  We used data from consecutive primary care patients suspected of deep venous thrombosis (DVT) to develop and validate a diagnostic model for the presence of DVT. Missing values were imputed 10 times with the MICE conditional imputation method. After the selection of predictors and transformations for continuous predictors according to three different methods, we estimated regression coefficients and performance measures.
  
  
  RESULTS
  The three methods to select predictors and transformations of continuous predictors showed similar results. Rubin's rules could easily be applied to estimate regression coefficients and performance measures, once predictors and transformations were selected.
  
  
  CONCLUSIONS
  We provide a practical approach for model development and validation with multiply imputed data.
authors: Julius Center for Health Sciences and Primary Care, University Medical Centre Utrecht, Str 6.131, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands. y.vergouwe@umcutrecht.nl
authors: Yvonne
authors: Y
authors: Vergouwe
authors: Patrick
authors: P
authors: Royston
authors: Karel G M
authors: KG
authors: Moons
authors: Douglas G
authors: DG
authors: Altman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D003627:Data Interpretation, Statistical; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011320:Primary Health Care / Q000379:methods; D015203:Reproducibility of Results; D012307:Risk Factors; D020246:Venous Thrombosis / Q000175:diagnosis