Table 2.

Efficacy and effectiveness of influenza vaccination according to different outcomes: crude results

		VAC	UNVAC	RR	95% Cl
Number of GPs with a respiratory tract infection	2002	37/66 (56.1%)	21/35 (60%)	0.93	0.66 – 1.32
	2003	48/96 (50%)	19/40 (47.5%)	1.05	0.72 – 1.54
	2002–2003	85/162 (52.5%)	40/75 (53.3%)	0.98	0.76 – 1.27
Number of GPs with a respiratory tract infection and positive nose and throat swabs	2002	3/66 (4.5%)	2/35 (5.7%)	0.78	0.13 – 4.94
	2003	11/96 (11.5%)	9/40 (22.5%)	0.51	0.23 – 1.13
	2002–2003	14/162 (8.6%)	11/75 (14.7%)	0.59	0.28 – 1.24
Number of GPs with a respiratory tract infection and a 4-fold hemagglutination-inhibition antibody titre rise	2002	2/59 (3.4%)	4/33 (12.1%)	0.28	0.05 – 1.45
	2003	3/36 (8.3%)	9/36 (25%)	0.33	0.10 – 1.13
	2002–2003	5/95 (5.3%)	13/69 (18.8%)	0.28	0.10 – 0.75
Number of GPs with a respiratory tract infection and positive swab or 4-fold hemagglutination-inhibition antibody titre rise	2002	4/59 (6.8%)	6/33 (15.2%)	0.45	0.13 – 1.55
	2003	7/36 (19.4%)	13/36 (36.1%)	0.54	0.24 – 1.19
	2002–2003	11/95 (11.6%)	18/69 (26.1%)	0.44	0.22 – 0.88