children. The indicators most frequently used are height-for-age, weight-for-age and weight-for-height. These indicators are standardized according with age and gender specific child growth standards provided by WHO and are universally comparable.<sup>12</sup> An insufficient height-for-age (or being stunted) or an insufficient weight-for-height (or being wasted) indicate acute malnutrition. Conversely, weight-for-age is a measure of underweight. In this study, I use height-for-age as an indicator of a child nutritional status standardized by age and sex according to WHO growth standards (henceforth HAZ). The reason is that HAZ is a better indicator of long term health. Indeed, it is an indicator of cumulative deficient growth and it is proved to be associated with diet, hygiene, infection and feeding practices. Conversely, weight-for-age is likely to be severely affected by temporary shocks due to morbidity and illnesses.

I study HAZ during early childhood. Focusing on early malnutrition is important because empirical evidence suggests that nutritional status during early childhood is a major predictor of health conditions and economic outcomes in further stages of life (Case et al., 2005; Gertler and Boyce, 2001). This is the reason why early policy interventions during childhood have been found to be particularly cost effective, with higher rates of return than later interventions (Heckman, 1995 and 2000).

# **4.2  The risk factors of child malnutrition**

Empirical evidence suggests that child malnutrition is caused by a lack of physical and human resources. There is a growing literature supporting the idea that social capital can act as a protective factor against socio-economic disadvantages. In this section I discuss the main risk factors associated with child malnutrition and define how they are measured in this study.<sup>13</sup> Table A1 in the Appendix shows descriptive statistics of the variables used in the empirical analysis.

## _Maternal social capital_

The YL survey contains a module to measure multiple aspects of maternal social capital. It is based on the _Short Adapted Social Capital Assessment Tool_ (SASCAT) which is a shortened version of the _Adapted Social Capital Assessment Tool_ (A-SCAT) by Harpham et al. (2002) developed specifically to measure social capital in low-income countries. The SASCAT tool measures both the individual structural social capital and cognitive social capital.

In the present analysis, the mother’s social participation is used to measure structural social capital. It is defined as a dummy equal to 1 if the mother in the previous 12 months was a member of at least one of the following community organizations: work-related groups or trade unions, religious groups, community associations, cooperatives for saving or housing/credit/funeral

> 12 See WHO Child Growth Standards report (www.who.int/childgrowth/en) for a detailed description on the methods used to construct the standards for height-for-age, weight-for-age and weight-for-height. 13 Notably, the term “risk factors” is adopted from epidemiologic literature and describe only associations and not causal relations. The “risk factors” analysis substantially differs from “analysis of determinants” which in turn investigates causal relationships.

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