Table 4.

Mixed Effects Model Results for Emotional Distress at Birth and 1 Month for the 29 Mothers of Late Preterm Infants and the 31 Mothers of Fullterm Infants.

	STAI-S		EPDS		PPQ		Worry
	Birth	1 Month	Birth	1 Month	Birth	1 Month	Birth	1 Month
Unadjusted Means	Mean "(SD)	Mean "(SD)	Mean "(SD)	Mean "(SD)	Mean "(SD)	Mean "(SD)	Mean "(SD)	Mean "(SD)
LPI	36.6 "(9.5)	31.4 "(7.5)	5.7 "(3.3)	3.5 "(3.1)	1.9 "(1.6)	2.0 "(1.9)	18.8 "(5.7)	15.0 "(5.4)
FT	27.6 "(6.1)	25.6 "(2.9)	2.4 "(3.8)	1.1 "(1.7)	0.8 "(1.2)	0.7 "(1.1)	12.2 "(5.0)	9.8 "(3.1)
Adjusted1,2	Mean "(SD)	Mean "(SD)	Mean "(SD)	Mean "(SD)	Mean "(SD)	Mean "(SD)	Mean "(SD)	Mean "(SD)
LPI	36.6 "(0.2)	31.4 "(0.2)	5.7 "(0.2)	3.5 "(0.1)	2.0 "(0.1)	1.9 "(0.3)	18.7 "(2.1)	14.8 "(2.1)
FT	27.6 "(0.1)	25.6 "(0.1)	2.4 "(0.1)	1.1 "(0.2)	0.8 "(0.1)	0.8 "(0.1)	12.3"(1.8)	10.1"(1.8)
Model Effects3	Estimate "(SE)		Estimate "(SE)		Estimate "(SE)		Estimate "(SE)
Group	5.83 "(2.04)***		2.42 "(0.73)***		1.23 "(0.45)***		4.68 "(1.40)***
Time	2.06 "(1.99) *		1.25 "(0.93)*		−0.02 "(0.47)		2.18 "(1.20)**
GxT	3.15 "(2.77)		0.92 "(1.29)		−0.07 "(0.66)		1.71 "(1.67)

¹Adjusted means were estimated by the mixed model that takes into account the fixed and random effects specified in the model.

²A statistically significant difference was observed between the late preterm and fullterm groups at birth and 1 month for all four measures "(all p < .05). The effect size was > 1.0 at each time point for all measures except PPQ where the effect size was greater than .78 at each time point.

³Estimates of effects and standard error "(SE) for terms in the final model: group, time, and group-by-time interactions "(GxT). The analysis of the worry outcome included the effects of being a first time mother as a covariate "(estimate = 2.32. SE = 1.12, p < .05).

^*p < .05;

^**p < .01;

^***p < .001.