The stability of the diagnosis of developmental disability between ages 2 and 8 in a geographic cohort of very preterm children born in 1997
- 1Premature Infant Follow-up Program at the Royal Women's Hospital, Parkville, Victoria, Australia
- 2Department of Paediatrics, The University of Melbourne, Melbourne, Victoria, Australia
- 3Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
- 4Department of Psychology, The University of Melbourne, Melbourne, Victoria, Australia
- 5Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, Victoria, Australia
- Correspondence to Dr Gehan Roberts, Department of Obstetrics and Gynaecology, The Royal Women's Hospital, 20 Flemington Road, Parkville, VIC 3052, Australia;
Contributors All the listed authors contributed substantially to the article.
- Accepted 16 September 2009
- Published Online First 14 October 2009
Objective Studies reporting the developmental outcomes for very preterm (VPT) children often focus on development at age 2 years. The aim of this study was to assess the stability of the rates of diagnosis of developmental disability from age 2 to 8 years in a regional cohort of VPT and extremely low–birth weight (ELBW) children and compare these with term controls.
Methods VPT (22–27 completed weeks of gestation) and ELBW (birth weight 500–999 g) children and matched term controls born in Victoria, Australia, in 1997 were enrolled at birth in a regional prospective longitudinal study. Outcomes were assessed at ages 2 and 8 years.
Results Of the 283 VPT/ELBW live births, 71% survived to age 8 years and 94% were assessed. Of the 199 controls, 100% survived to age 8 years and 86.9% were assessed. At age 2 years, the rates of nil, mild, moderate and severe disabilities in the VPT/ELBW children were respectively 51.9%, 20.9%, 13.4% and 13.9%; and at age 8 years, 43.9%, 36.9%, 10.7% and 8.6%. The Cohen κ statistic revealed poor agreement between disability status at ages 2 and 8 years for VPT/ELBW children (0.20, p<0.001) but a higher level of agreement (0.37, p<0.001) for the control children. This was primarily driven by differences in classification of cognitive disability between ages 2 and 8 years.
Conclusions Developmental outcomes at age 2 years are only a moderate predictor of long-term outcome and are not a reliable end point for follow-up studies of VPT and ELBW children.
Participants Convenor Lex W Doyle, MD, FRACP; Collaborators (in alphabetical order): Peter Anderson, PhD; Catherine Callanan, RN; Elizabeth Carse, FRACP; Margaret P Charlton, MEd Psych; Noni Davis, FRACP; Cinzia de Luca, BSc; Julianne Duff, FRACP; Marie Hayes, RN; Esther Hutchinson, BSc (Hons); Elaine Kelly, MA; Marion McDonald, RN; Gillian Opie, FRACP; Gehan Roberts, MPH, PhD, FRACP; Linh Ung, BSc (Hons); Andrew Watkins, FRACP, and Heather Woods, RN.
Funding This study was funded by the Victorian Government, who had no involvement in the design, the collection, the analysis and the interpretation of data; in the writing of the report and in the decision to submit the paper for publication.
Competing interests None.
Ethics approval This study was conducted with the approval of the Royal Women's Hospital Research and Ethics Committee.
Provenance and peer review Not commissioned; externally peer reviewed.