Structural Equation Models from Cebu Analyses.

<p>Structural equation model depicting (a) direct-effects only model (Model 1) and (b) favorable fetal growth conditions (FFGC) latent variable model (Model 2) for Cebu. BW = latent newborn weight; BL = latent newborn length, GA = latent gestational age; BW1 = newborn weight measured by birth attendants; BW2 = newborn weight measured by study staff; HTCM = newborn length; LMPGA = gestational age estimated from mother's report of date of her last menstrual period; BALGA = gestational age estimated from Ballard assessment of newborn; NOTPROJ = newborn not weighed on project scale; NOTONE = weight not measured day of birth; WHENBW2 = infant age in days when measured by study staff; WHENBW2SQ = WHEN2BW squared; WHENBAL = age in days when Ballard assessment was done; NOTONE = newborn not weighed on day 1; GIRL = newborn is a girl; AMA = maternal arm muscle area during pregnancy; AFA = maternal arm fat area during pregnancy; MOHT = mother's height; SMOKERS = mother smoked during pregnancy; FIRSTPRG = newborn was firstborn; YOUNGER = mother was <20 years old when pregnant; older = mother was >35 years old when pregnant. (Figures adapted from Bollen et al. [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0153800#pone.0153800.ref005" target="_blank">5</a>], p. 13–14).</p

Descriptive Statistics for Cebu and NC/PA.

<p>Descriptive Statistics for Cebu and NC/PA.</p

Modified Structural Equation Model from NC/PA Analyses.

<p>Structural equation model relating mother’s traits to birth outcomes through the mediating favorable fetal growth conditions (FFGC) latent variable, following theoretical and empirical modifications (Model 3). BW = birth weight; BL = birth length, GA = gestational age; GIRL = newborn is a girl; MOMWT = mother’s pre-pregnancy weight; MOHT = mother's height; SMOKERS = mother smoked during pregnancy; FIRSTPRG = newborn was firstborn; YOUNGER = mother was <20 years old when pregnant; older = mother was >35 years old when pregnant; AA = mother is African-American.</p

Chi-Squared Difference Testing of Multiple Groups Models.

<p>Chi-Squared Difference Testing of Multiple Groups Models.</p

Factor Loadings for FFGC Indicators.

<p>Factor Loadings for FFGC Indicators.</p

Birth Weight, Birth Length, and Gestational Age as Indicators of Favorable Fetal Growth Conditions in a US Sample

<div><p>The “fetal origins” hypothesis suggests that fetal conditions not only affect birth characteristics such as birth weight and gestational age, but also have lifelong health implications. Despite widespread interest in this hypothesis, few methodological advances have been proposed to improve the measurement and modeling of fetal conditions. A <i>Statistics in Medicine</i> paper by Bollen, Noble, and Adair examined favorable fetal growth conditions (FFGC) as a latent variable. Their study of Filipino children from Cebu provided evidence consistent with treating FFGC as a latent variable that largely mediates the effects of mother’s characteristics on birth weight, birth length, and gestational age. This innovative method may have widespread utility, but only if the model applies equally well across diverse settings. Our study assesses whether the FFGC model of Cebu replicates and generalizes to a very different population of children from North Carolina (N = 705) and Pennsylvania (N = 494). Using a series of structural equation models, we find that key features of the Cebu analysis replicate and generalize while we also highlight differences between these studies. Our results support treating fetal conditions as a latent variable when researchers test the fetal origins hypothesis. In addition to contributing to the substantive literature on measuring fetal conditions, we also discuss the meaning and challenges involved in replicating prior research.</p></div

Structural Equation Models from NC/PA Analyses.

<p>Structural equation model depicting (a) direct-effects only model (Model 1) and (b) favorable fetal growth conditions (FFGC) latent variable model (Model 2) for NC/PA. BW = birth weight; BL = birth length, GA = gestational age; GIRL = newborn is a girl; MOMWT = mother’s pre-pregnancy weight; MOHT = mother's height; SMOKERS = mother smoked during pregnancy; FIRSTPRG = newborn was firstborn; YOUNGER = mother was <20 years old when pregnant; older = mother was >35 years old when pregnant.</p

Characteristics of study population.

Characteristics of study population.</p

Logistic regression model for at-risk opioid use during 3-month follow-up after ed visit for trauma.

Logistic regression model for at-risk opioid use during 3-month follow-up after ed visit for trauma.</p

Enrollment, follow-up, and exclusion criteria flow diagram for persons in analysis.

Enrollment, follow-up, and exclusion criteria flow diagram for persons in analysis.</p