title: Drivers can poorly predict their own driving impairment: a comparison between measurements of subjective and objective driving quality.
abstract: BACKGROUND
  Adverse drug effects such as reduced alertness may cause drivers to be unaware that their driving is impaired.
  
  
  OBJECTIVE
  This study was conducted to examine if drivers are adequately aware of their driving ability when treated with central nervous system drugs.
  
  
  METHODS
  Data from three clinical trials applying the on-the-road driving test were used to compare the primary outcome measure, the Standard Deviation of Lateral Position, with subjective assessments of alertness before driving, as well as perceived driving quality, and mental effort to perform the test.
  
  
  RESULTS
  The analyses revealed significant correlations for perceived driving quality (r = -0.498, p < 0.0001), mental effort to perform the test (r = 0.408, p < 0.0001), and alertness taken before driving (r = -0.115, p < 0.017). The predictive validity (R (2)) of perceived driving quality (24.8%), mental effort (16.6%), and alertness before driving (1.3%) was low.
  
  
  CONCLUSIONS
  The analyses show that subjective assessments do not robustly relate to actual driving performance either in terms of judgments about alertness before the drive or ratings of performance after the drive.
authors.affiliation: Utrecht Institute for Pharmaceutical Sciences, Division of Pharmacology, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands. j.c.verster@uu.nl
authors.forename: Joris C
authors.initials: JC
authors.lastname: Verster
authors.forename: Thomas
authors.initials: T
authors.lastname: Roth
mesh_terms: D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects* / Q000523:psychology*; D001334:Automobile Driving / Q000523:psychology* / Q000592:standards; D005260:Female; D006801:Humans; D007600:Judgment / Q000187:drug effects*; D008297:Male; D055553:Prescription Drugs / Q000009:adverse effects* / Q000494:pharmacology; D011597:Psychomotor Performance / Q000187:drug effects*; D012647:Self-Assessment; D055815:Young Adult
chemical_list: D055553:Prescription Drugs