Table 2. Results of the meta-analysis of the role of dietary carotenoids on performance

No	Parameter	N	SMD/d+(RE 95% CI)	p-value	I2(%)	p-value	Kendall’s τ	p-value
1	Feed intake	93	0.32 (0.02, 0.61)	0.034	99.249	<0.05	–0.069	0.331
2	FCR	78	–0.31 (–0.60, –0.02)	0.034	99.066	<0.05	–0.287	<0.001
3	Final body weight	56	0.33 (0.05, 0.60)	0.02	97.662	<0.05	0.048	0.606
4	Egg production	101	0.38 (0.14, 0.63)	0.002	98.868	<0.05	0.118	0.080

N, number of databases; SMD/d+(RE 95% CI), standardized mean difference (true effect size) by random-effects model with 95% confidence interval; I², inconsistency (%); FCR, feed conversion ratio.