The GBD study is the most comprehensive effort to conduct a population-level CRA across countries and risks. Differences between GBD 2016 estimates and other global estimates are generally related to approaches to data processing, access to data sources, and analysis decisions. For several risks, including smoking,57 ambient ozone pollution, household air pollution from solid fuels, lead exposure,58 intimate partner violence,59 unsafe water source,60 and breastfeeding, GBD estimates were lower than published WHO estimates.57, 58, 59, 60 These discrepancies can be attributed to different definitions, methodological decisions, granularity, and input data. For some findings, annual estimates might disagree, but regional patterns were consistent between WHO and GBD. UNICEF61 produces estimates for child stunting that are lower than GBD estimates with some disagreement where progress has been made globally. There is more consistency in estimates between UNICEF and GBD for child wasting and child underweight.61 GBD estimates for the prevalence of low birthweight and short gestation are slightly lower when compared with WHO estimates, but show similar geographical patterns.62 Scientific literature reveals similar results to GBD for impaired kidney function63 and low
