Table 6. Pooled crude and adjusted seasonal vaccine effectiveness overall and by influenza type and age group among the target group for vaccination, imputed data, I-MOVE multi-centre case control study, influenza season 2010-11.

Outcome			N	VE%	95% CI
All influenza	All ages	Crude‡	1004	63.2	48.4-73.7
		Adjusted model∫	1004	56.2	34.3-70.7
	15-59 yearŝ	Crude‡	447	67.6	37.9-83.1
		Adjusted model∫	447	54.0	6.6-77.3
	60+ yearŝ,*	Crude‡	413	52.7	23.3-70.9
		Adjusted model∫	413	62.8	32.8-79.4
A(H1N1)	All ageŝ,$	Crude‡	780	71.1	55.4-81.3
		Adjusted model∫	780	58.9	32.0-75.1
Influenza B	All ages	Crude‡	705	62.2	37.4-77.2
		Adjusted model∫	705	63.4	31.0-80.6

^‡Study site included in the model as fixed effect.

^∫ Model adjusted for 2009-10 pandemic influenza vaccination, presence of at least one chronic disease, sex, at least one hospitalisation for chronic disease in the previous 12 months, current smoker, age group (10 year bands), practitioner visits in previous 12 months (0–1, 2–4 and 5+ visits), week of symptom onset.

For the certain analyses, weeks or months of onset had to be dropped due to only positive or negative outcomes during this week or month.

^*April dropped (3 records dropped).

+ Week 13, 14 and 45 dropped (8 records dropped)

^{^}Onset month used for adjusting instead of onset week.

$ November and April dropped (5 records dropped).

∼ Weeks 45 and 13 dropped (7 records dropped).