TABLE 3

Behavioral Outcomes at 19 Weeks to 24 Months of Age

VariableAgeNAll (N = 802)Control Group (n = 209)FAB Group (n = 205)Sleep Group (n = 192)Combination Group (n = 196)Overall P for Group DifferenceaP for Specified Time
Exclusive breastfeeding, wk median (IQR)b77815.0 (20.3)14.5 (19.0)13.0 (20.9)14.0 (19.7)17.0 (20.0).069
Time in active play outside, median (IQR), min/d12 mo64420 (43)20 (35)a26 (51)a20 (35)a30 (50)a.005
18 mo55730 (45)30 (45)30 (45)30 (45)40 (40).171
24 mo46740 (49)40 (49)35 (49)39 (40)45 (47).045.828
Time spent watching television; 
geometric mean 
(geometric SD), min/wkc6 mo217111.3 (3.7)162.1 (3.8)a96.3 (3.5)ab131.8 (3.5)ab71.2 (3.7)a<.001
12 mo23974.7 (3.3)90.1 (3.5)a70.3 (3.2)a80.0 (3.1)a57.8 (3.2)a.046
18 mo426122.6 (3.4)143.6 (3.3)124.2 (3.5)119.0 (3.3)100.8 (3.6).191
24 mo399197.9 (3.1)214.1 (3.4)239.5 (2.6)189.1 (3.1)152.3 (3.2).007.118
Night sleep duration by questionnaire, mean ± SD, h19 wk71810.82 ± 1.3810.88 ± 1.4410.75 ± 1.2710.75 ± 1.3510.90 ± 1.47
27 wk70011.08 ± 1.2711.16 ± 1.3311.00 ± 1.3011.07 ± 1.1711.10 ± 1.25
12 mo64511.37 ± 0.8911.46 ± 0.9311.38 ± 0.9211.33 ± 0.7311.28 ± 0.94
24 mo51011.20 ± 0.7811.28 ± 0.8711.18 ± 0.8111.12 ± 0.7111.19 ± 0.71.907
Night sleep duration by accelerometry, mean ± SD, h24 mo30310.36 ± 0.9010.31 ± 0.9410.44 ± 0.8610.43 ± 0.9110.19 ± 0.91.187
Night awakenings per week,
median category19 wk7195–65–65–65–65–6
27 wk7015–65–675–65–6
12 mo6451–21–21–21–23–4
24 mo5091–21–21–21–21–2.451
Extent to which infants sleep was a problem,d geometric mean (geometric SD)19 wk7192.14 (1.93)2.03 (1.91)2.29 (1.95)2.23 (1.90)2.01 (1.97).215
23 wk6852.20 (1.98)2.15 (1.99)2.36 (2.03)2.16 (1.95)2.13 (1.95).430
27 wk7022.39 (1.94)2.21 (1.97)a2.64 (1.89)a2.45 (2.0)a2.28 (1.91)a.042
18 mo6091.90 (1.94)2.01 (2.00)1.92 (1.98)1.73 (1.90)1.92 (1.84).242
24 mo5101.83 (1.83)1.94 (1.83)1.83 (1.85)1.67 (1.80)1.86 (1.2).023.410
Sleep problems,e n (%) with score of 5–819 wk719116 (16.1)28 (14.4)31 (17.1)30 (17.5)27 (15.7)
23 wk685135 (19.7)33 (18.0)43 (24.7)31 (18.2)28 (17.7)
27 wk702140 (19.9)31 (16.6)39 (21.4)41 (24.6)29 (17.5)
18 mo60987 (14.3)32 (18.4)25 (15.9)17 (11.8)13 (9.7)
24 mo51052 (10.2)19 (13.5)15 (10.9)9 (7.9)9 (7.6).346
Frequency child put into bed when tired but awakef12 mo6461.6 (2.0)1.5 (2.0)1.7 (2.0)1.6 (1.9)1.6 (2.0).537
Child falls asleep at night without parent touching themf12 mo6491.8 (2.1)1.7 (2.1)1.8 (2.1)1.8 (2.1)1.8 (2.2).895
24 mo5111.5 (1.9)0.4 (0.7)0.4 (0.7)0.3 (0.6)0.5 (0.7).314
Allowed child to self-settle without intervention when
woke at night, n (%)12 mo49970 (14.0)21 (15.1)25 (18.2)6 (5.6)18 (15.5).059
24 mo34483 (24.1)24 (25.8)26 (27.1)19 (26.0)14 (17.1).501
  • Data presented as indicated. Intervention group values on the same line with no superscript letters in common indicate significant differences (P < .05) between groups. IQR, interquartile range. —, not applicable.

  • a P values are from Cox’s proportional hazards regression for exclusive breastfeeding duration, mixed linear models after a log-transformation for time in active play outside and time spent watching television, mixed linear models for night sleep duration (both questionnaire and accelerometer obtained) and extent to which sleep was a problem, mixed ordinal logistic models for number of night awakenings, mixed binary logistic models for sleep problems, and logistic regression for sleep behaviors (put to bed tired but awake, fall asleep without parent touching them, allowed child to self-settle without intervention when woke at night). All analyses adjusted for parity (primiparous and multiparous) and deprivation (NZ Deprivation deciles 1–3, 4–7, and 8–10) strata.

  • b Medians and IQRs are for those with known (including zero) durations (n = 735).

  • c Geometric mean and SD are calculated from back-transforming the mean calculated on the log scale.

  • d From a possible score of 1 (no problem) to 8 (large problem).

  • e A sleep problem was defined as having a score of 5 to 8 on this 8-point scale.

  • f Where 1 = always, 4 = sometimes, and 7 = never presented as geometric mean (geometric SD).