possible to identify communities that are highly atypical. Figure 3 also shows the identification code for the two communities lying at the extreme of the distribution of Model 6 community-level residuals. These can be selected for further intensive qualitative examination, thus forming a link between the quantitatively-based multilevel analysis and a more qualitatively-based investigation.<sup>28</sup>

# **7.4 Factors Accounting for Community-Level Variation**

We now look at the role of each factor in accounting for the variation in height-for-age z-scores across the 60 surveyed communities. To do so we proceed in two steps. First, we examine how the variance of the community random effect is reduced when we add each covariate alone to a reference model with only age and sex. Second, we look at how the variance is increased when we remove each covariate in turn from the full model.

Table 7 displays the parameter estimates. Altitude accounts for the largest proportion of the initial community-level variation. This finding holds both when we include altitude in the model with only age and sex (o2, is reduced by 42%) and when we omit it from the full model (a2c is increased by 64%). The high percentage increase in community-level variation resulting from removing altitude from the full model gives further credence to the idea that the observed covariates fail to capture in full the poorer living conditions that affect the growth of children living in communities at higher altitudes. Mother's height is the second most important covariate. Ethnicity and the presence of farms or plantations within

- 28 We first examined the household characteristics in the two 'outlier' communities (i.e. the communities with the largest and smallest community-level residuals). Households in the community with the worst growth outcomes as compared to the model's predictions (identification code 21_2_7) are, on average, better off than households in the community with the best growth outcomes (identification code _8_6_1). In the former community, the average proportion of indigenous people is 0.02, the average height of mothers is 144.5 centimeters, the average level of mothers' education is 1.1 years, the average level of husbands' education is 1.9 years, and the average per capita household expenditure is 22.8 quetzals. In the latter community, all mothers are indigenous, the average height of mothers is 142.7 centimeters, the average level of mothers' education is 0.6 years, the average level of husbands' education is 0.7 years, and the average per capita household expenditure is 22.9 quetzals. However, the average z- score is -3.2 for children in the former community and -2.8 for children in the latter community.

- We then compared the information collected by the EGSF community questionnaire in the two communities to investigate the reasons for their deviation from the predicted outcomes. These two communities are very similar in terms of the infrastructure and services that they provide to their residents. They do, however, differ with respect to migration patterns. Specifically, the key informants report that men living in comnmunity 21_2_7 commonly migrate outside the community to work in plantations and farms. Conversely, men in the community _8_6_1 seem to remain, and work, in the community. Three factors help explain why children who depend on fathers' migration to work on plantations may be disadvantaged: (1) these children are generally of poorer families that have less land; (2) they often have long periods without income because their fathers are not able to start eaming and sending money home immediately after they leave; and (3) they may receive little financial help, if any, because some of their fathers may spend their eamings in other activities. Although this argument remains speculative, we also postulate that children in community 21_2_7 suffer disproportionately from the absence of their fathers, as fathers' education is a key factor in their children's growth process in rural Guatemala. On average, the fathers in this community have more than twice as many years of education as the fathers in community _8_6_1(1.9 years and 0.7 years respectively). As a result of their absence, however, they may not always be able to fully contribute to their children's health and nutritional needs.

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