Table 3. Pooled adjusted seasonal vaccine effectiveness against laboratory-confirmed influenza A(H3N2) by age group and target group for vaccination, I-MOVE/I-MOVE+ multicentre case control studies (primary care (n = 4,937) and hospital (n = 635)), influenza season 2016/17 .

Analyses	Adjustment / stratification	Cases			Controls			Adjusted VE	95% CI
Analyses	Adjustment / stratification	All	Vaccinated	%	All	Vaccinated	%	Adjusted VE	95% CI
Primary care
All ages	Adjusted by study site only	2,216	229	10	2,721	297	11	10.9	−8.3 to 26.6
	Adjusted by calendar time and study site	2,216	229	10	2,721	297	11	27.9	11.9 to 41.1
	Adjusted by calendar time, age and study site	2,216	229	10	2,721	297	11	38.4	22.2 to 51.3
	Fully adjusted: calendar time, age, study site, presence of chronic conditions, sex	2,216	229	10	2,721	297	11	38.0	21.3 to 51.2
By age group (years)^a	0–14	773	20	3	1,043	27	3	44.1	−12.3 to 72.2
	15–64	1,164	69	6	1,410	126	9	46.9	25.2 to 62.3
	≥ 65	278	140	50	268	144	54	23.4	−15.4 to 49.1
Target group for vaccination^a	All ages	606	201	33	698	235	34	25.7	1.5 to 43.9
Hospital
≥ 65 years	Adjusted by study site only	267	108	40	368	191	52	−0.7	−46.8 to 30.9
	Adjusted by calendar time and study site	267	108	40	368	191	52	3	−42.2 to 33.8
	Adjusted by calendar time, age and study site	267	108	40	368	191	52	2.5	−43.6 to 33.8
	Fully adjusted: time, age, study site, sex, chronic condition (lung, heart, renal disease, diabetes, cancer, obesity) and hospitalisation in the past year	240	95	40	316	162	51	2.0	−51.7 to 36.8
By age group (years)^b	65–79	130	38	29	165	70	42	7.9	−67.3 to 49.3
By age group (years)^b	≥ 80	115	59	51	167	102	61	2.4	−81.3 to 47.5

CI: confidence interval; VE: vaccine effectiveness at hospital level.

^a Adjusted by study site, age, calendar time, presence of chronic conditions and sex.

^b Adjusted by calendar time, age and study site.