The UK is not in the top 10 countries when it comes to the quality of life and wellbeing of older people, a table has calculated.
Britain came 13th in the Global AgeWatch Index which looked at income, health, personal capabilities, education, employment and social environment to help highlight what older people experience in countries around the world.
The research put the UK behind Ireland in 12th but ahead of France, which was 18th, and Australia in 14th. Sweden came top with Afghanistan the worst.
Several major European countries did not make the top 20 including Italy in 27th, Belgium in 24th and Spain, which came 22nd.
Experts said the index is the first quantitative measure of its kind to focus on the wellbeing of older people on a worldwide scale. It compared the experiences of older people from 91 countries and ranked them in order of quality of experience.
The figures could allow older people to more effectively lobby their governments and hold them to account over policies as the world's population continues to age, the report suggested.
Professor Asghar Zaidi, from the Centre for Research on Ageing at the University of Southampton, was consultant for the project commissioned by HelpAge International.
He said: "The Global AgeWatch Index is the beginning of a process in which we are gathering all the available evidence of the lives of older people around the world.
"It follows the footsteps of the Human Development Index of the United Nations Development Programme (UNDP) and presents, in an accessible and engaging way, a 'dashboard' of indicators that measure the multidimensional quality of life and wellbeing of older people in a range of different socio-economic contexts."
By 2050 the number of older people in the world will have risen to more than two billion and the index was essential to develop new ways to tackle the global challenge of population ageing and to enable older people to have a voice, experts said.
Silvia Stefanoni, interim chief executive of HelpAge International, said: "The world is rapidly ageing: people over 60 years of age already exceed children under five, and by 2050 they will outnumber children under 15. However, the continual exclusion of ageing from national and global agendas is one of the biggest obstacles to meeting the needs of the world's ageing population.
"By giving us a better understanding of the quality of life of women and men as they age, this new index can help us focus our attention on where things are going well and where we have to make improvements."
Prof Zaidi said: "We expect the index to become an important research and analysis framework for practitioners and policy-makers alike, as it will facilitate cross-national comparative research on the quality of life and wellbeing of older people, and help identify data and knowledge gaps on issues of ageing. We need to give more and more importance to such data-gathering work - in fact, since the lives of older people are at stake, we can't afford not to."
The index did not simply demonstrate the best and worst places for people to grow old, but was also a tool to encourage countries to recognise the challenges of their ageing populations, the professor added.
It also revealed that gross domestic product per capita - a proxy for countries' wealth and standard of living - did not necessarily lead to better welfare for older people.
The top 20 countries were:
7. New Zealand
13. United Kingdom