Comparison 4. Prolonged feeding: hydrolysed formula versus cow's milk formula.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 All allergic disease	9		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
1.1 Infancy (incidence)	8	2852	Risk Ratio (M‐H, Fixed, 95% CI)	0.88 [0.76, 1.01]
1.2 Childhood (incidence)	2	950	Risk Ratio (M‐H, Fixed, 95% CI)	0.85 [0.69, 1.05]
1.3 Childhood (prevalence)	1	62	Risk Ratio (M‐H, Fixed, 95% CI)	1.76 [0.76, 4.09]
2 Asthma	7		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
2.1 Infancy (incidence)	4	318	Risk Ratio (M‐H, Fixed, 95% CI)	0.57 [0.31, 1.04]
2.2 Childhood (incidence)	1	78	Risk Ratio (M‐H, Fixed, 95% CI)	0.38 [0.08, 1.84]
2.3 Childhood (prevalence)	3	1229	Risk Ratio (M‐H, Fixed, 95% CI)	1.03 [0.79, 1.33]
3 Eczema	10		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
3.1 Infancy (incidence)	9	2896	Risk Ratio (M‐H, Fixed, 95% CI)	0.93 [0.79, 1.09]
3.2 Childhood (incidence)	2	950	Risk Ratio (M‐H, Fixed, 95% CI)	0.83 [0.63, 1.10]
3.3 Childhood (prevalence)	3	1228	Risk Ratio (M‐H, Fixed, 95% CI)	0.86 [0.66, 1.12]
4 Rhinitis	5		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
4.1 Infancy (incidence)	3	256	Risk Ratio (M‐H, Fixed, 95% CI)	0.52 [0.14, 1.85]
4.2 Childhood (incidence)	1	78	Risk Ratio (M‐H, Fixed, 95% CI)	0.48 [0.04, 5.03]
4.3 Childhood (prevalence)	2	357	Risk Ratio (M‐H, Fixed, 95% CI)	0.97 [0.66, 1.41]
5 Food allergy	2		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
5.1 Infancy (incidence)	2	479	Risk Ratio (M‐H, Fixed, 95% CI)	1.42 [0.87, 2.33]
6 Cow's milk allergy	1		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
6.1 Infancy (incidence)	1	338	Risk Ratio (M‐H, Fixed, 95% CI)	2.31 [0.24, 21.97]