Health Report.A new study examines and compares adult death rates worldwide over the last forty years. For each country, researchers estimated the probability that a fifteen-year-old today will die an early death before the age of sixty. They found that the country with the lowest risk of premature death for women is Cyprus. For men the country with the best rate is Iceland.The study estimated mortality rates for people age fifteen to fifty-nine in one hundred eighty-seven countries. The report appeared last week in the Lancet medical journal.Worldwide, in the last forty years, death rates have decreased nineteen percent for men. But the study found that death rates for women have fallen by thirty-four percent.Chris Murray from the University of Washington in the Pacific Northwest led the study. He says major progress has been made since nineteen seventy in reducing deaths of mothers and children. But he points to growing inequalities in adult mortality -- a "massive spread" between countries with the highest rates and those with the lowest.For example, for men in Swaziland, the difference between the best rate and the worst rate is nine times higher. The study did find improvements in sub-Saharan Africa in the last five years, however, possibly as a result of expanded efforts against AIDS.But in the last twenty years, H.I.V. and the collapse of the Soviet Union helped raise death rates in thirty-seven countries worldwide. Also, the study says the United States fell from thirty-fourth to forty-ninth in female mortality and from forty-first to forty-fifth for men. Those estimates put the country behind western Europe as well as countries like Albania, Chile and Tunisia.The researchers noted a big changein the list of countries with the lowest adult mortality over the past forty years. Only three countries have stayed in the top ten for the lowest male death rates all that time. Those countries are Sweden, the Netherlands and Norway.The researchers say estimating and preventing early deaths in adults is just as important as improving child survival. Millions of children die before their fifth birthday. But the researchers say three times as many adults die before their sixtieth.And that's the VOA Special English Health Report, written by Caty Weaver. Do you have a comment on this story or a general question about health? Go to 51voa.com or find us on Twitter and Facebook at VOA Learning English.