Inquiry to all children alive at the age of 14 years was conducted by postal questionnaire concerning their growth and heath, living habits, school performance and family situation.
Target population: N = 11 778 (100%)
Cases with known address: N = 11 764 (99.9%)
Data received: N = 11 010 (93.6%)
Addresses of the children and data of mortality were obtained from the National Population Centre of Finland and Central Statistical Office of Finland by sending identity numbers of children to these authorities. If the address was not obtained from these authorities, it was inquired from the church register offices and finnish embassiess abroad. The address was not found for 14 cases living abroad.
The postal questionnaire was sent first to the children and then if they did not respond to their parents.
In order to get information on all the children, the same questionnaire was sent to the regional school offices and to the school health nurses if the children or their parents did not respond.
Rantakallio P.: A follow-up study up to the age of 14 of children whose mothers smoked during pregnancy. Acta Paediatr. Scand. 1983, 72: 747-753.
Rantakallio P.: A 14-year follow-up of children with normal and abnormal birth weight for their gestational age - a population study. Acta Paediatr. Scand. 1985, 74: 62-69.
Rantakallio P., von Wendt L.: Mental Retardation and Subnormality in a Birth Cohort of 12,000 Children in Northern Finland. Pediatrics Digest September:4-5, 1986.
Last updated: 10.7.2020