Table 1

Characteristics of participants in the ECHO-PATHWAYS consortium

	Overall (n=2684)		CANDLE* (n=1456)		TIDES* (n=790)		GAPPS-PW† (n=438)
Variable (categorical)‡	N	%	N	%	N	%	N	%
Child sex	2683		1456		790		437
Male		50		50		51		49
Female		50		50		49		51
Maternal race	2645		1454		773		418
White		51		31		70		82
Black/African-American		38		62		13		2
Asian		3		1		6		3
Native Hawaiian/Pacific Islander		0		0		1		0
American Indian/Alaska Native		0		0		1		1
Multiple		5		5		4		9
Other		2		0		6		3
Maternal ethnicity	2664		1454		779		431
Hispanic		6		2		9		14
Not Hispanic		94		98		91		86
Maternal education§	2660		1454		781		425
<High school		10		12		8		4
High school completion		35		46		19		26
College degree		32		30		31		44
Graduate/professional degree		23		12		43		26
Prenatal smoking (any)¶	2655	7	1455	10	775	6	425	3
Prenatal alcohol use	2657	10	1455	8	785	13	417	9
Preterm birth (<37 weeks)	2681	11	1456	9	789	10	436	18
Breast feeding (any)	2161	78	1188	66	541	91	432	94
Breastfeeding duration	1669		770		494		405
<2 months		14		19		7		11
2–4 months		17		23		10		12
5–6 months		13		17		8		11
>6 months		57		41		74		66
Variable (continuous)‡	N	Median IQR	N	Median IQR	N	Median IQR	N	Median IQR
Gestational age at birth (days)	2681	275	1456	274	789	277	436	274
		269–281		269–280		270–284		264–281

*The study population was defined as participants with birth outcome data (either birth weight or gestational age at birth) in CANDLE and TIDES.
†GAPPS was a closed cohort, which was reopened for ECHO-PATHWAYS and the study population in this summary includes those consented into GAPPS-PW as of 31 December 2020.
‡N is defined as the total N with non-missing data. Percent is shown for each category.
§College degree includes college or technical school degree. Graduate/professional defined as some graduate work or graduate/professional degree.
¶Maternal smoking during pregnancy was defined based on self-report.
**
††
CANDLE, Conditions Affecting Neurocognitive Development and Learning in Early Childhood; GAPPS, Global Alliance to Prevent Prematurity and Stillbirth; TIDES, The Infant Development and Environment Study.