Table 1.

Summary of the design of 12 publically available studies assessing an association between pandemic AS03-adjuvanted H1N1 vaccination and narcolepsy

		Population			Case ascertainment		Vaccine ascertainment
Study	Design	Geographic origin (period)	Size	Age	Source	Validation	Source	Coverage
MPA-registry cohort, Sweden8	RC	7 counties (2009–2011)	5.8 M	All	Contact with hospitals and sleep labs, spontaneous reports	No expert review	Regional vaccination registries	60%
MPA case-inventory, Sweden5	RC	Nationwide (2009–2010)		All	Registers on hospitalisation and specialist care	By 2 experts in neurology/sleep disorders	Regional vaccination registries	60%
Stockholm county cohort, Sweden16	RC	Stockholm county (1998–2010)	2 M	< 20 (for narcolepsy)	Hospital registers, child rehabilitation, neurophysiology centers	No expert review	Local vaccination registry (Vaccinera)	52.6%
Western Sweden cohort11	RC	Western Swedish health care region (2000–2010)	0.4 M	2–17 yrs	National and local hospital registers, register 3 specialized centers	No expert review	Unclear
Finnish childhood cohort24	RC	Nationwide (2009–2010)	0.9 M	4–19 yrs	National hospital registers	By 2 narcolepsy experts. Discrepancies adjudicated by a narcolepsy expert panel	Electronic primary health care databases	75%
Finnish adult cohort25	RC	Nationwide (2009–2011)	3.3 M	Adults	National hospital registers + direct contact pediatric neurologists	By 2 narcolepsy experts. Discrepancies adjudicated by a narcolepsy expert panel	Electronic primary health care databases	48%
Finnish case series10	Eco	Nationwide (2002–2010)		All	National care register + direct contact health care professionals	By 5 experts in neurology/sleep disorders	Vaccine certificates
Irish cohort26	RC	Nationwide (2009–2010)	4.2 M	4–19 yrs, ≥ 20 yrs	Direct contact sleep and pediatric neurology centers	By an adult and pediatric neurologist	Reimbursement database and mass vaccination database	22.5%
English case-coverage9	CCo	Nationwide (2008–2011)	9.1 M	4–18 yrs	Direct contact sleep centers	By 3 narcolepsy experts	GP questionnaires	1.9%*
French case-control13	CC	Nationwide (2009–2011)	65 M	All	Direct contact sleep centers	By 2 narcolepsy experts	Telephone interviews	6.3%**
VAESCO EU multi-country3 Denmark, France, Italy, the Netherlands, Norway & UK: non-signaling + Sweden & Finland	CC	Nationwide or regional, (April 2009-June 2010)	30 M	All	Varied by country - registers, direct contact with sleep centers	Country dependent	Variety of methods	Very low to high
Norwegian cohort27	RC	Nationwide (120 weeks from 2009 onwards)	1 M	<20 yrs	Medical institutions and practitioners	By a pediatrician and expert in sleep disorders	National vaccination register	50%

MPA = Medical products Agency, M = millions, RC = retrospective cohort. CS = case series, CC = case control, CCo = case coverage, Eco = ecological study,

^*37% in the 2–15 y old risk group and includes some use of unadjuvanted vaccines in pregnant women and young infants,

^**mostly 9 y of age and older.