Introduction Saigal et al. proposed a Health Status Classification System for Pre-School children (HSCS-PS) as a multi-dimensional measure to describe quality of life of, as well as to permit evaluation of preferences for, health states of children as young as 2-5 years (Qual Life Res 2005;14:243-257). We evaluated construct validity of the HSCS-PS in a population very low birth weight (VLBW) children at the corrected age of 24 months.

Methods Parents of 87 VLBW children (gestational age <32 weeks) visiting the neonatal follow-up program at the Erasmus MC-Sophia Children's Hospital between June 2004 and March 2005 completed the HSCS-PS that consists of 10 dimensions with 3-5 levels each. To evaluate construct validity of the HSCS-PS child development was assessed with the Bayley Scale of Infant Development (BSID-II: mental (MDI) and motor (PDI) development), the Child Behavior Checklist (CBCL) and the LEXI (based on the Language Development Survey). Results Mean corrected age was 2.0 years (SD=0.06); mean gestational age was 29.7 weeks (SD=1.5), mean birth weight was 1243 gram (SD=356); mean MDI=96 (SD=15), mean PDI=91 (SD=15); mean LEXI quotient=97 (SD=14). High scores (level 3, 4 or 5) on the HSCS-PS, indicating moderate or severe impairments, were found for HSCS-PS-dimensions Self-care (9.9%), Speech (9.3%), General-health (5.9%), Dexterity (3.5%), Mobility (3.4%) and Pain & Discomfort (2.4%), Thinking & Problem solving (1.2%) and Behaviour (1.1%). Gestational age correlated with HSCS-PS dimensions Pain & discomfort (r=-0.33); MDI with Seeing (r=-0.27), Speech (r=-0.36), Mobility (r=-0.39), Dexterity (r=-0.44), Self-care (r=-0.54), Emotion (r=-0.27), Learning & Remembering (r=-0.41) and Thinking & Problem solving (r=-0.35); PDI with Mobility (r=-0.34) and Self-care (r=-0.37); LEXI-score with Speech (r=-0.40) (p<=.01). CBCL-scores (internalizing and externalizing behaviors and total score) correlated with Emotion, Learning & Remembering and Thinking & Problem solving (r=0.28-0.40) (p<=.01).

Discussion In this population of well-documented VLBW-children at age 24 months, the observed correlations between parental ratings of the 10 HSCS-PS dimensions with gestational age as indicator of pregnancy-outcome as well as with measures of specific impairments, support the construct validity of the HSCS-PS. This study showed that, in a clinical setting, even at the very young age this classification system adequately describes health and neurodevelopment of VLBW-children.