Table 1

 Comparison of main neonatal outcomes by response status (data returned within or outside of the 22–28 month follow up window or not at all) at 2 years of age

VariableWithin window (N = 373)Outside window (N = 55)No data (N = 171*)p Value
*Includes three questionnaires returned without any data.
†Postmenstrual age.
‡Cranial ultrasound scans after day 14.
Chronic lung disease at 36 weeks†218/3735830/555580/164490.12
Oxygen dependent at discharge83/3712213/552426/162160.22
Major cranial abnormality‡39/346118/491619/150130.58