The Dunedin study at 50: landmark experiment tracked 1,000 people from birth

Study into health and behaviour, which began in New Zealand in 1972, marks its half century this week as its subjects prepare for old age

In 1972, a researcher in a small city at the bottom of New Zealand set out to track the development of more than 1,000 newborn babies and their health and behaviour at age three, not realising then that over the next 50 years, the research would morph into one of the world's most important longitudinal studies.

The study did not stop at three years, instead it gathered pace, following the lives of the participants from birth into adulthood, and creating a comprehensive body of data that has yielded more than 1,300 peer-reviewed research papers, reports and books.