Table 1.

Baseline characteristics of the study participants.

	Intervention group (n = 99)	Control group (n = 95)	P-value*
Infants
Gender, % male	50.50	54.70	NS
Mean gestation weeks	39.23	38.99	NS
Mean birth weight, g	3027.22	2950.94	NS
Siblings, % present	40.00	38.40	NS
Mean Kaup’s index 10g/cm−2	16.86	16.97	NS
Parents
Maternal mean age, y	31.72	31.55	NS
Paternal mean age, y	34.84	34.27	NS
Maternal occupation, % present	24.2	30.3	NS
Married, % present	99.0	97.9	NS
Living in the apartment, % present	93.9	93.6	NS
The caregiver in daytime, % present	94.9	97.9	NS

*χ² test was performed for comparison of proportion and student’s t test was performed for comparison of means.