OBJECTIVE: This study investigates and measures whether the association of childhood stunting with household socio-economic position (SEP) differs in Sri Lanka compared with other South Asian countries. DESIGN: Secondary analysis of data of children from the latest available Demographic and Health Surveys data (survey years, 2016-2018). The exposures (SEP) were maternal education and wealth. The outcome was stunting. Binary logistic regression models incorporated SEP, country and SEP-by-country interaction terms. SETTING: A nationally representative sample of children from Bangladesh, India, Nepal, Pakistan and Sri Lanka. PARTICIPANTS: Mothers/caregivers of children under 36 months (133 491). RESULTS: The prevalence of stunting in Sri Lanka of 19 % was much lower than that observed for all the other low- to low-middle income South Asian countries (37 % in Bangladesh, 36 % in India, 31 % in Nepal and 30 % in Pakistan). The association of SEP with odds of stunting was similar in Sri Lanka compared with other South Asian countries. The only exception was weaker associations of wealth with stunting in Sri Lanka compared with Bangladesh. For example, in Sri Lanka, the poorest group had 2·75 (2·06, 3·67) times higher odds of stunting compared with the richest group, but in Bangladesh, this estimate was 4·20 (3·24, 5·44)
the difference between these two estimates being 0·65 (0·44, 0·96) on the OR scale. CONCLUSIONS: The lower prevalence of stunting in Sri Lanka is unlikely to be due to less inequality. It is more likely that the lower prevalence of stunting in Sri Lanka is related to there being fewer mothers belonging to the lowest SEP groups.