| Methods |
Case‐control study |
| Participants |
Cases (n = 145): Guillain‐Barré syndrome cases (defined according to the Brighton Collaboration definition) diagnosed in France between 2007 and 2010.
Controls (n = 1080): the dates for control recruitment were matched (by calendar month) to the index date of the associated case. Additional matching criteria included gender, age (65 years for cases aged 18 years or more and 61 years for cases younger than 18 years) and place of residence (southern or northern France). |
| Interventions |
Exposure to influenza vaccine. Data about pandemic vaccine analysed separately.
Exposure to virus and occurrence of ILI also tested as risk factor. |
| Outcomes |
Association between Guillain‐Barré syndrome and influenza vaccine exposure |
| Notes |
The study has been financially supported by LA‐SER, GSK Biologicals, and Sanofi Pasteur. |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| CC ‐ case selection
All outcomes |
Unclear risk |
From different countries |
| CC ‐ control selection
All outcomes |
Unclear risk |
Not same population, insufficient description |
| CC ‐ comparability
All outcomes |
Unclear risk |
Matching |
| CC ‐ exposure
All outcomes |
Unclear risk |
Interview |
| Summary assessment |
High risk |
High risk of bias |
