Normative Scores for the Pediatric Evaluation of Disability Inventory in Norway.
OBJECTIVE
The aim of this study was to develop clinically useful normative scores for the Pediatric Evaluation of Disability Inventory (PEDI) for children in Norway, and provide information on the relative difficulty level of individual test items.


METHODS
Using PEDI protocols from 224 Norwegian children without disability, we computed and scrutinized the normative scores for their representativeness, and compared them with scores from 313 children in the original US PEDI sample. Item functioning was compared using Rasch model-based differential item functioning (DIF) analyses and comparisons of item mastery.


RESULTS
The normative scores yielded consistent and regular results. The mean scores for each age group in the Norwegian sample were lower than in their US counterparts, and age mean plots ran parallel. However, this difference may be misleading for clinical use, as item comparisons revealed differences in both higher and lower directions between the samples for about a third of all items. Estimates of relative item difficulty for children in Norway were developed.


CONCLUSIONS
Identifying potential differences when using an instrument in another culture is important to avoid a risk of over- or underestimating a child's capability. In addition, item response patterns are required to make national normative scores clinically useful.
a Regional Center of Knowledge Translation Rehabilitation , Oslo , Oslo , Norway.|b Akershus University College , Oslo , Norway.
Marie M
MM
Berg
c Lillehammer University College , Lillehammer , Norway.
Anne-Stine
AS
Dolva
c Lillehammer University College , Lillehammer , Norway.
Jo
J
Kleiven
d Neuropediatric Unit, Department of Women's and Children's Health , Karolinska Instituttet , Stockholm , Sweden.
Lena
L
Krumlinde-Sundholm
D002648:Child; D002675:Child, Preschool; D003431:Cross-Cultural Comparison; D004185:Disability Evaluation; D019988:Children with Disabilities; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009664:Norway; D010372:Pediatrics / Q000379:methods*; D012016:Reference Values; D012720:Severity of Illness Index; D014481:United States
Cross-cultural testing; Norway; PEDI; national differences; norms