Developmental disabilities modification of the Children's Global Assessment Scale

Area of Science:

• Child Psychology
• Psychometrics
• Developmental Disorders

Background:

• Interventions for pervasive developmental disorders (PDD) aim to improve functioning.
• The Children's Global Assessment Scale (CGAS) is used to measure global functioning in treatment studies.
• A revised version, the DD-CGAS, was developed and psychometrically assessed in children with PDD.

Purpose of the Study:

• To assess the psychometric properties of the revised DD-CGAS for measuring global functioning in children with PDD.
• To enhance rater consistency through specific descriptors and administration procedures.

Main Methods:

• Developed developmental disabilities-relevant descriptors for the DD-CGAS.
• Assessed inter-rater reliability and temporal stability using clinical case vignettes.
• Evaluated validity by correlating DD-CGAS with functioning and symptom measures in 83 children with PDD.
• Assessed sensitivity to change in 14 children by comparing pre-post treatment scores with other measures.

Main Results:

• Excellent inter-rater reliability (ICC = .79) and temporal stability (average ICC = .86).
• DD-CGAS scores showed moderate to large correlations with measures of functioning and symptoms.
• Changes in DD-CGAS scores correlated significantly with changes in the Aberrant Behavior Checklist-Irritability (r = -.71) and Clinical Global Impressions-Improvement (r = -.52) subscales.
• The pre-post DD-CGAS change demonstrated a substantial effect size of 0.72.

Conclusions:

• The DD-CGAS is a reliable and valid instrument for assessing global functioning in children with PDD.
• The DD-CGAS demonstrates apparent convergent validity, making it suitable for treatment studies.
• The revised scale enhances the measurement of global functioning in this population.