title: Validating the stroke-thrombolytic predictive instrument in a population in the United kingdom.
abstract: OBJECTIVE
  This study aimed to test the explanatory qualities of the Stroke-Thrombolytic Predictive Instrument (S-TPI) when applied to patients treated in routine practice.
  
  
  METHODS
  S-TPI predictions were compared with observed outcomes in terms of normal/near-normal (modified Rankin Scale score, ≤1) and catastrophic outcome (modified Rankin Scale score, ≥5) at 3 months. Logistic regression was used to calibrate and expand the S-TPI.
  
  
  RESULTS
  The S-TPI overestimated probability of catastrophic outcomes and overestimated the probability of a normal/near normal outcome above 0.4 and underestimated those below. Calibrating the S-TPI minimized discrepancies between predicted and observed outcomes, in the case of normal/near-normal outcomes, where including additional predictors (serum glucose and signs of current infarction on pretreatment brain scan) further reduced discrepancies between predicted and observed outcomes.
  
  
  CONCLUSIONS
  The explanatory power of the S-TPI in thrombolytic-treated patients can be improved to reflect outcomes seen in routine practice.
authors.affiliation: Institute of Health and Society, Newcastle University, Newcastle Upon Tyne, UK. peter.mcmeekin@newcastle.ac.uk
authors.forename: Peter
authors.initials: P
authors.lastname: McMeekin
authors.forename: Darren
authors.initials: D
authors.lastname: Flynn
authors.forename: Gary A
authors.initials: GA
authors.lastname: Ford
authors.forename: Helen
authors.initials: H
authors.lastname: Rodgers
authors.forename: Richard G
authors.initials: RG
authors.lastname: Thomson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002138:Calibration / Q000592:standards; D015331:Cohort Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011336:Probability; D012372:ROC Curve; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D020521:Stroke / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology; D015912:Thrombolytic Therapy / Q000592:standards* / Q000706:statistics & numerical data*; D016896:Treatment Outcome; D006113:United Kingdom / Q000453:epidemiology