- longitudinal study over period of 12 years.
-During this time to test moral reasoning he gave 75 young American males a series of hypothetical and
philosophical moral dilemmas in the form of short stories
Examples of the moral dilemmas included - for 10 year olds: "Is it better to save the life of one
important person or a lot of unimportant people?" and at ages 13, 16, 20 and 24: "Should the doctor
'mercy kill' a fatally ill woman requesting death because of her pain?"
Cross-cultural and cross-sectional element: Kohlberg compared the males from the USA to those from Canada,
the UK, Mexico, Turkey and Taiwan.
Each participant was seen as being in a particular stage when 50% of their responses to dilemmas fell neatly