title: Do clinicians use more question marks?
abstract: OBJECTIVE
  To quantify the use of question marks in titles of published studies.
  
  
  METHODS
  Literature review.
  
  
  METHODS
  All Pubmed publications between 1 January 2013 and 31 December 2013 with an available abstract. Papers were classified as being clinical when the search terms clin*, med* or patient* were found anywhere in the paper's title, abstract or the journal's name. Other papers were considered controls. As a verification, clinical journals were compared to non-clinical journals in two different approaches. Also, 50 highest impact journals were explored for publisher group dependent differences.
  
  
  METHODS
  Total number of question marks in titles.
  
  
  RESULTS
  A total of 368,362 papers were classified as clinical and 596,889 as controls. Clinical papers had question marks in 3.9% (95% confidence interval 3.8-4.0%) of titles and other papers in 2.3% (confidence interval 2.3-2.3%; p < 0.001). These findings could be verified for clinical journals compared to non-clinical journals. Different percentages between four publisher groups were found (p < 0.01).
  
  
  CONCLUSIONS
  We found more question marks in titles of clinical papers than in other papers. This could suggest that clinicians often have a question-driven approach to research and scientists in more fundamental research a hypothesis-driven approach. An alternative explanation is that clinicians like catchy titles. Publishing groups might have pro- and anti-question mark policies.
authors.affiliation: Brain Center Rudolf Magnus, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands ; Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, 2103 SW, The Netherlands.
authors.forename: Maeike
authors.initials: M
authors.lastname: Zijlmans
authors.affiliation: Brain Center Rudolf Magnus, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands.
authors.forename: Willem M
authors.initials: WM
authors.lastname: Otte
authors.affiliation: Brain Center Rudolf Magnus, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands.
authors.forename: Maryse A
authors.initials: MA
authors.lastname: Van't Klooster
authors.affiliation: Brain Center Rudolf Magnus, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands.
authors.forename: Eric
authors.initials: E
authors.lastname: van Diessen
authors.affiliation: Brain Center Rudolf Magnus, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands.
authors.forename: Frans Ss
authors.initials: FS
authors.lastname: Leijten
authors.affiliation: Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, 2103 SW, The Netherlands ; NIHR University College London Hospitals Biomedical Research Centre, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK.
authors.forename: Josemir W
authors.initials: JW
authors.lastname: Sander
keywords: inductive research; punctuation; query