title: [Difficulties of a longitudinal epidemiological follow-up study in French occupational medicine].
abstract: BACKGROUND
  This study was designed to describe the difficulties of epidemiological follow-up of employees by occupational health services.
  
  
  METHODS
  This study was based on two transverse studies conducted by the Pays de la Loire musculoskeletal disorders (MSD) surveillance network. Eighty-three occupational health physicians included 3,710 employees between 2002 and 2005 and had to review them between 2007 and 2009. Thirteen of these physicians changed jobs and 7 changed geographical sector in the same occupational health service.
  
  
  RESULTS
  Another 94 physicians were contacted and 85 agreed to participate in the network. The follow-up rate was 43%: 1,044 employees were reviewed by the physician who saw them on inclusion and 567 employees were reviewed by another physician of the network. The other employees were distributed as follows: 25% were lost to follow-up and their occupational status remained unknown; 23% were still employed with an identified occupational health physician but had not attended a medical visit during the follow-up study; 5% had left the occupational health surveillance system. Only 23 employees refused to participate in the follow-up and 105 employees had a physician who refused to participate.
  
  
  CONCLUSIONS
  There is therefore a considerable mobility of occupational health physicians, which interfered with follow-up despite their good mobilization and a high percentage of employee are lost to follow-up after having left their jobs. More appropriate systems must be set up to follow populations of employees, such as new collaborations with general practitioners.
authors.forename: Céline
authors.initials: C
authors.lastname: Sérazin
authors.forename: Catherine
authors.initials: C
authors.lastname: Ha
authors.forename: Patrick
authors.initials: P
authors.lastname: Bidron
authors.forename: Anne-Claire
authors.initials: AC
authors.lastname: Gillard
authors.forename: Caroline
authors.initials: C
authors.lastname: Tilliette
authors.forename: Véronique
authors.initials: V
authors.lastname: Tassy
authors.forename: Ellen
authors.initials: E
authors.lastname: Imbernon
authors.forename: Yves
authors.initials: Y
authors.lastname: Roquelaure
mesh_terms: D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D005602:France; D006801:Humans; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000453:epidemiology*; D016272:Occupational Health; D009786:Occupational Health Services; D009787:Occupational Medicine