Comparison 3.

Live attenuated vaccines (cohort studies by age group)

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Influenza	1	83	Risk Ratio (M‐H, Random, 95% CI)	0.56 [0.35, 0.91]
1.1 under 2 years	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
1.2 under 6 years	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
1.3 over 6 years	1	83	Risk Ratio (M‐H, Random, 95% CI)	0.56 [0.35, 0.91]
2 Influenza‐like illness	2	22077	Risk Ratio (M‐H, Random, 95% CI)	0.63 [0.57, 0.69]
2.1 under 2 years	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
2.2 under 6 years	0	0	Risk Ratio (M‐H, Random, 95% CI)	0.0 [0.0, 0.0]
2.3 over 6 years	2	22077	Risk Ratio (M‐H, Random, 95% CI)	0.63 [0.57, 0.69]