The United States performs poorly in U.N. rankings on progress towards global health goals due to its high levels of violence, alcohol abuse and childhood obesity, a study has found.

The research, published in The Lancet medical journal on Wednesday, offers the first assessment of 188 countries' rankings against the United Nations' Sustainable Development Goals (SDGs), which aim to boost health by improving the environment, food and water and by easing poverty.

More than 60 percent of the nations assessed have already met targets on reducing maternal and child death rates, the study showed, but none have met nine other targets including the elimination of tuberculosis and HIV or reducing prevalence of childhood obesity and violence.

The United States ranked 28th, below many other wealthier nations, due to its relatively high rates of death caused by violence, HIV, alcohol abuse, childhood obesity and suicide.

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The United States also lagged among high-income countries on maternal and child mortality, reflecting large differences in the accessibility and quality of healthcare.

Iceland topped the rankings, followed by Singapore and Sweden, thanks to good sanitation and healthcare provision and to progress on tackling "rich-world" health problems such as obesity, chronic diseases, violence and road traffic injuries.

The Central African Republic, Somalia and South Sudan had the lowest scores.

The SDGs are targets set by the United Nations to tackle a range of pressing problems including food and water security, poverty and climate change up to 2030. They follow the Millennium Development Goals, which expired at the end of 2015 and were also focused on reducing poverty and improving health.

The aim of the SDG assessment is accountability on progress towards the targets, to give policymakers, aid groups and health workers an overview of gaps and priorities in health care.

"(It is) a starting point for further investigation on how and why countries are under-performing or performing well," said Stephen Lim, a professor of global health at the Institute for Health Metrics and Evaluation (IHME) at Washington University which led the assessment.

"This will be an annual effort to ensure progress is maintained and lessons from successes are learned and rapidly transferred to other countries," he said.