BMJ Global Health time.43 45 However, in most countries, the male/female ratio is close to even and survey sampling should help account for urban/rural migration. Finally, all estimates are at the national level, which may obscure large within country differences in birth registration by region or inequities within-­ regions, particularly by gender and particularly in countries with large sex ratios at birth. Future work could examine subnational changes in birth registration and inequities at the regional or state level to guide the targeting of efforts within countries to improve registration. However, our findings make two key contributions to prior research that documents global improvements in access to birth registration.2 3 First, we show that improvements in access to birth registration were neither ubiquitous nor universal, as evidenced by the 14 countries where non-­registration increased and by the 16 countries where, even at the most recent survey, 1 in 2 children under five did not have their births registered. Second, our findings suggest that even improvements in ‘on average’ access to birth registration should be interpreted with caution 10 and through the lens of equity-­oriented analyses which reveal that across the 39 countries where non-­registration declined, improvements in many countries were unfairly and unevenly distributed. Our findings echo prior work on how national averages can mask health inequities,46 and how large inequities in child health outcomes and access can persist even in the context of increasing national coverage.43 47 Prior research has also demonstrated how absolute health inequities increase in the short term and how by the time coverage improves among the most deprived groups, coverage among the most privileged groups is already close to 100%.48 Similarly, historical research in high-­ income countries suggests that the expansion of birth registration was unequal and documents how minority and marginalised populations were initially excluded.49–51 Our results raise questions about whether the path to universal coverage of birth registration is through large wealth and urban/rural inequities: the majority of surveys in the sample underscore that children in poor households and rural areas are more likely to be living without Bhatia A, et al. BMJ Global Health 2019;4:e001926. doi:10.1136/bmjgh-2019-001926 BMJ Global Health: first published as 10.1136/bmjgh-2019-001926 on 16 December 2019. Downloaded from https://gh.bmj.com on 21 July 2025 by guest. Protected by copyright, including for uses related to text and data mining, AI training, and similar technologies. Figure 4 Magnitude of annual change in (A) wealth inequalities and (B) urban/rural inequalities among countries which increased and decreased non-­registration.