included in appendices. In the key summary tables, however, estimates are presented contrasting the wealthiest, or fifth, quintile with the poorest, or first, quintile. Household density (or crowding) is also included not as a direct proxy for SES, but as an additional regressor, documented to be an environmental stressor and important determinant of child wellbeing (Evans 2004).

# _Child Nutritional Status_

Two measures of nutritional outcomes are included: birth weight (to reflect nutrition during gestation) and height-for-age z-score, HAZ (to reflect early childhood nutrition). For children with recorded birth weight information (48%), actual birth weight was highly correlated with maternal report of perceived birth weight (r=0.60, p<0.001), suggesting that perceived birth weight is a reasonable proxy for actual recorded birth weight.<sup>3</sup> Thus, perceived birth weight was included in the regressions (binary indicator variable for perceived “low” or “very low” birth weight relative to “normal,” “high,” or “very high”). Significant associations exist between low height-for-age (stunting) and delayed cognitive development, psychomotor development, behavior, and later success in school (Grantham-McGregor et al. 2007). In Madagascar, the prevalence of stunting among children was 58% at our first measurement when children were 0–3 years.<sup>4</sup>

# _Maternal Education and Endowments_

Maternal education is expressed with indicators of completed primary or secondary education. In addition, maternal height and maternal receptive vocabulary are included as proxies for maternal ability. Maternal height is an important proxy for maternal cognitive development (Case and Paxson 2008) and represents a mechanism for the intergenerational transmission of economic status since it represents maternal genetic endowment in addition to her own prenatal and childhood exposure. Children born to mothers who are shorter are more likely to have lower birth weight/length and higher neonatal mortality than those born to taller mothers (Bhalotra and Rawlings 2013). To measure maternal receptive vocabulary, the same test used for children was used for mothers, the PPVT-III. Maternal vocabulary ability was estimated using item-response theory (IRT) to ensure a common metric for the variable across the sample (Masters and Wright 1984).

# _Parenting Inputs_

To measure parenting inputs, an adaptation of the Home Observation for Measurement of the Environment Inventory (HOME) for Middle Childhood (MC) in 2011 was administered. The adapted HOME scale captures learning environments which represent key pathways through which poverty can affect school readiness; the HOME scale captures both risk factors that increase vulnerability (e.g., harsh parental punishment, lack of sensitive parenting, limited books or toys in the home) as well as buffering factors that can help children thrive in spite of poverty (e.g., exposure to responsive parenting, presence of books and toys in the home) (Blair and Raver 2012;

> 3. <mark>Children whose mothers assessed their weight as small, and children with low measured weight have been shown to be significantly less likely to survive than are children who weigh more at birth (Alderman et al. 2011).</mark> 4. The prevalence of stunting in our sample is slightly higher than the prevalence reported by UNICEF (50%, 2013) and the DHS (53% in children 6–59 months old, 2008–9), as our sample is representative of rural and small urban centers in the country, excluding the capital and larger cities.