Growing Up in Ireland - the National Longitudinal Study of Children, is the first survey of its kind ever undertaken in Ireland and, as such, aims to explore the many and varied factors that contribute to or undermine the wellbeing of children currently living there. A two age cohort longitudinal design was adopted with one cohort of 11,134 infants (aged nine months) and the other of 8,568 nine-year olds, with a view to improving and understanding of children’s development across a range of domains. Since the survey is longitudinal in nature respondents in both cohorts are interviewed on a number of occasions over the folowing few years. The 11,134 children representing the nine-month cohort were born between 1st December 2007 and the 30th June 2008 and data collection for that group took place between September 2008 and April 2009.

Probability: Stratified: Proportional. Children were selected from the Child Benefit Register (provided by the Department of Social and Family Affairs) so as to be 9 months of age (in their 10th month) at time of interview (i.e. between September 2008 to end April 2009). Date of birth for the children in question therefore, lay between 1st December 2007 and 30th June 2008. This yielded a total eligible Register population of 41,185 children over the period in question2. The sample was selected on a systematic basis, pre-stratifying by marital status, county of residence, nationality and number of children in the claim - all variables which were available internally from the information recorded on the Register itself. A simple systematic selection procedure based on a random start and constant sampling fraction was used.

Face-to-face interview: CAPI/CAMI

Self-administered questionnaire: Computer-assisted (CASI)