Standardised method of follow-up assessment of preterm infants at the age of 5 years: use of the WHO classification of impairments, disabilities and handicaps. Report from the collaborative Project on Preterm and Small for gestational age infants (POPS) in The Netherlands, 1983.

A nationwide, prospective study was initiated in The Netherlands in 1983, involving 1338 liveborn infants with a gestational age less than 32 weeks and/or a birthweight less than 1500 g. Pre- and perinatal data, methods and results of follow-up until the corrected age of 2 years have been published previously. In this paper, methods of follow-up at the age of 5 years are described. At that age, 966 children were alive, of which 927 (96%) were assessed during a home visit 2 to 6 weeks after their fifth birthday by three specially trained paediatricians. A questionnaire served to collect data on medical history, respiratory function, behaviour and socio-economic factors. Standardised tests were carried out covering the following 10 areas: congenital malformations, neuromotor function, mental development, hearing, visual function, language and speech development, behaviour, musculoskeletal system, respiratory tract and ENT problems, and growth. The outcome was recorded for separate areas and for the child as a whole using the WHO classification of impairments, disabilities and handicaps.