Analysing four Norweigian population-based samples using the six-month version of the Ages and Stages Questionnaire showed few relevant clinical differences.
OBJECTIVE
We investigated whether there were clinically relevant differences in the area mean scores of the six-month Ages and Stages Questionnaire (ASQ) between four Norwegian population-based samples.


METHODS
Area mean scores and standard deviations (SDs) were investigated for the five developmental areas of the ASQ: communication, gross motor, fine motor, problem solving and personal-social. Sample sizes varied from 166 to 1192 and the ASQ was completed on paper or by computer. ASQ scores in the four samples were compared using ANOVA and Tukey's procedure was used to adjust for multiple comparisons.


RESULTS
The ASQ mean area scores were generally similar in the four data sets, with few clinically relevant differences, defined as a mean difference of greater than five points, which is the smallest increment in area score, or an effect size of >0.5 in absolute value. All the clinically relevant differences occurred when samples used a modified ASQ administration format. Several additional minor differences were statistically significant, which was expected due to the large samples.


CONCLUSIONS
These results support the original Norwegian normative findings for the ASQ six-month form and the ASQ's use as a low-cost developmental screening tool in Norway, at least when the original format is administered.
National Network for Infant Mental Health in Norway, Center for Child and Adolescent Mental Health, Eastern and Southern Norway, Oslo, Norway.
Lisbeth
L
Valla
The Norwegian Center for Child Behavioral Development, Oslo, Norway.
Harald
H
Janson
Center for Child and Adolescent Mental Health, Eastern and Southern Norway, Oslo, Norway.|Norwegian Center for Violence and Traumatic Stress Studies, Oslo, Norway.
Tore
T
Wentzel-Larsen
National Network for Infant Mental Health in Norway, Center for Child and Adolescent Mental Health, Eastern and Southern Norway, Oslo, Norway.|Department of Psychology, University of Oslo, Oslo, Norway.
Kari
K
Slinning
D002657:Child Development; D002675:Child, Preschool; D002658:Developmental Disabilities / Q000175:diagnosis; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009664:Norway; D011795:Surveys and Questionnaires
Ages and Stages Questionnaire; Development; Infants; Screening tool