title: Performance curves of medical researchers during their career: analysis of scientific production from a retrospective cohort.
abstract: To establish the pattern of change in individual scientific production over the career of medical researchers.
  
  
  
  Retrospective cohort based on prospectively collected data in a hospital information system.
  
  
  
  Multicentre university hospital in France.
  
  
  
  Two distinct populations of 1835 researchers (full professors vs non-academic physicians) having produced 44 723 publications between 1995 and 2014.
  
  
  
  Annual number of publications referenced in Medline/PubMed with a sensitivity analysis based on publications as first/last author and in high impact journals. The individual volume of publications was modelled by age using generalised estimating equations adjusted for birth cohort, biomedical discipline and academic position of researchers.
  
  
  
  Averaged over the whole career, the annual number of publications was 5.28 (95% CI 4.90 to 5.69) among professors compared to 0.82 (95% CI 0.76 to 0.89) among non-academic physicians (p<0.0001). The performance curve of professors evolved in three successive phases, including an initiation phase with a sharp increase in scientific production between 25 and 35 years (adjusted incidence rate ratio 102.20, 95% CI 60.99 to 171.30), a maturation phase with a slower increase from 35 to 50 years (2.10, 95% CI 1.75 to 2.51) until a stabilisation phase with constant production followed by a potential decline at the end of career (0.90, 95% CI 0.77 to 1.06). The non-academic physicians experienced a slower pace of learning curve at the beginning of their careers (42.38, 95% CI 25.37 to 70.81) followed by a smaller increase in the annual number of publications (1.29, 95% CI 1.11 to 1.51).
  
  
  
  Compared to full professors, non-academic physicians had a poor capacity to publish, indicating a low productivity when medical doctors have limited time or little interest in undertaking research. This finding highlights the potential for rethinking the missions of medical doctors towards an enlargement of scientific prerogatives in favour of progress in global knowledge.
authors.affiliation: Pôle Information Médicale Évaluation Recherche, Hospices Civils de Lyon, Lyon, France.|Health Services and Performance Research Lab (EA 7425 HESPER), Université Claude Bernard Lyon 1, Lyon, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Duclos
authors.affiliation: Pôle Information Médicale Évaluation Recherche, Hospices Civils de Lyon, Lyon, France.
authors.forename: Eléonore
authors.initials: E
authors.lastname: Herquelot
authors.affiliation: Pôle Information Médicale Évaluation Recherche, Hospices Civils de Lyon, Lyon, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Polazzi
authors.affiliation: Direction de la Recherche Clinique et de l'Innovation, Hospices Civils de Lyon, Lyon, France.
authors.forename: Muriel
authors.initials: M
authors.lastname: Malbezin
authors.affiliation: Department of Neonatal Intensive Care Unit, Hospices Civils de Lyon, Hôpital Femme Mère Enfant, Bron, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Claris
mesh_terms: D000328:Adult; D001319:Authorship; D003625:Data Collection; D004526:Efficiency; D005180:Faculty, Medical / Q000706:statistics & numerical data*; D005260:Female; D005602:France; D006785:Hospitals, University; D006801:Humans; D059032:Learning Curve; D016239:MEDLINE; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010820:Physicians / Q000706:statistics & numerical data*; D011643:Publishing / Q000639:trends*; D012108:Research Personnel / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D013647:Task Performance and Analysis
keywords: STATISTICS & RESEARCH METHODS; individual performance; medical researcher; scientific production