Table 1.

Demographic Characteristics of Groups

Randomized GroupFunctional Grouping
SomeAlways
GroupABCP<7 books7 or moreP
Number1618181834
A97
B612
C3150.007
Gender (female)a62.50%27.78%50.00%0.11844.44%47.06%0.857
GAb38.538.639.30.35438.438.90.657
Delivery (cesarean)a37.50%44.44%38.89%0.80750.00%35.29%0.466
NICUa18.75%16.67%11.11%0.89416.67%14.71%0.852
Maternal ageb29.625.627.50.05328.327.10.308
Paternal ageb32.228.229.80.18131.429.20.305
Maternal education levelb13.413.715.20.03512.614.90.015
Paternal education levelb12.613.713.80.70912.114.10.034
Birth orderb2.51.91.90.3412.41.90.302
Number of adultsb2.62.32.20.6292.72.20.149
Number of kidsb2.41.82.10.5082.51.90.141
  • Abbreviations: A, books only; B, books and commitment to read 1 book a day; C, books and commitment to read 1 book a day and video; NICU, the neonatal intensive care unit.

  • a Fischer's exact test.

  • bKruskal-Wallis test.