We discuss potential explanations for a factor’s effect (or the lack of an effect) to the extent that the study empirically tests the explanation. However, we find very few studies that do this. Alternatively, we discuss studies that empirically examine a dimension of the factor (for example, water quality) that may explain the effect of the factor on nutrition status found in other studies. Supplementing the synthesis of the empirical evidence, we conclude this subsection by discussing qualitative evidence on other potentially meaningful determinants of child nutrition status.

_Child-level factors_ : With respect to breastfeeding, in terms of positive evidence, studies find that current breastfeeding (Mahmood 2001; Fikree, Rahbar, and Berendes 2000), exclusive breastfeeding in the first six months (Alderman and Garcia 1994), breastfeeding for more than twelve months (Farid-ul-Hasnain and Pradhan 2013), and breastfeeding more than usual when the child is sick (Fazal et al. 2013) are associated with better nutrition status. In contrast, the World Bank provincial nutrition status notes do not find that initiating breastfeeding within one hour of birth or age-appropriate breastfeeding of children are associated with stunting status in any of the provinces, based on bivariate tests.

With respect to child feeding more broadly, the World Bank provincial nutrition status notes examine the effect of whether the child’s diet had minimum diversity, as defined by WHO guidelines. The notes find that minimum dietary diversity is negatively associated with stunting status in Balochistan and Punjab based on multivariate tests, but is not associated with stunting status in KPK and Sindh based on bivariate tests. Baig-Ansari et al. (2006) do not find that either breastfeeding or complementary feeding, measured through indexes that capture a range of practices, are associated with stunting status. Fazal et al. (2013) do not find that minimum dietary diversity or age when complementary feeding was initiated are associated with wasting status.

With respect to diarrhea and other illnesses, some studies find that they are negatively associated with nutrition status (Arif et al. 2014; Mahmood 2001; Alderman and Garcia 1994). In contrast, the World Bank provincial nutrition status notes do not find that diarrhea and respiratory infection are associated with stunting status in any of the provinces, based on bivariate tests. Fikree, Rahbar, and Berendes (2000) generally do not find that recurrent episodes of diarrhea are associated with stunting or wasting status. Fazal et al. (2013) do not find that recent illness is associated with wasting status. With respect to health at birth, studies find that low birth–weight–for–gestational– age (Fikree, Rahbar, and Berendes 2000), premature birth (Mahmood 2001), and low birth weight (Rahman et al. 2004a; Mahmood 2001) are negatively associated with child nutrition status.

With respect to maternal and child health service use, studies find that formal antenatal care (Headey, Hoddinott, and Park 2016; Mahmood 2001) and delivery at a health facility (Headey, Hoddinott, and Park 2016; Alderman and Garcia 1994) are positively associated with nutrition status. Adding a refinement, Mahmood (2001) finds that birth in a private health facility (but not birth in a public health facility) is negatively associated with stunting status. With respect to vaccinations, studies do not find that they are associated with nutrition status (Mahmood 2001; Alderman and Garcia 1994).

18