Utility of the General Ability Index (GAI) and Cognitive Proficiency Index (CPI) with survivors of pediatric brain tumors: Comparison to Full Scale IQ and premorbid IQ estimates.
Pediatric brain tumor survivors are at risk for working memory and processing speed impairment. The General Ability Index (GAI) provides an estimate of intellectual functioning that is less influenced by working memory and processing speed than a Full Scale IQ (FSIQ). The Cognitive Proficiency Index (CPI) provides a measure of efficient information processing derived from working memory and processing speed tasks. We examined the utility of the GAI and CPI to quantify neurocognitive outcomes in a sample of pediatric brain tumor survivors.



GAI, CPI, and FSIQ scores from the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) were examined for 57 pediatric brain tumor survivors (ages 6-16 years) treated with cranial radiation therapy (RT).



GAI scores were higher than FSIQ and CPI scores, both p < .001. Lower CPI scores were associated with history of craniospinal irradiation and time since RT. Lower FSIQ and GAI scores were associated with higher RT dose and time since RT. The rate of clinically significant GAI-FSIQ discrepancies in our sample was greater than that observed in the WISC-IV standardization sample, p < .001. Estimated premorbid IQ scores were higher than GAI, p < .01, and FSIQ scores, p < .001.



Pediatric brain tumor survivors exhibit weaker cognitive proficiency than that expected for age, while general reasoning ability remains relatively spared. The GAI may be useful to quantify the intellectual potential of a survivor when appropriate accommodations are in place for relative cognitive proficiency weaknesses. The CPI may be a particularly sensitive outcome measure of treatment-related cognitive change in this population.
a Department of Pediatrics, Section of Psychology , Baylor College of Medicine , Houston , TX , USA.
Lisa S
LS
Kahalley
b Texas Child Study Center, Dell Children's Medical Center of Central Texas , The University of Texas at Austin , Austin , TX , USA.
Amanda
A
Winter-Greenberg
a Department of Pediatrics, Section of Psychology , Baylor College of Medicine , Houston , TX , USA.
Heather
H
Stancel
a Department of Pediatrics, Section of Psychology , Baylor College of Medicine , Houston , TX , USA.
M Douglas
MD
Ris
a Department of Pediatrics, Section of Psychology , Baylor College of Medicine , Houston , TX , USA.
Marsha
M
Gragert
D000293:Adolescent; D001076:Aptitude; D001932:Brain Neoplasms / Q000523:psychology*; D000073116:Cancer Survivors / Q000523:psychology*; D002648:Child; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D007360:Intelligence / Q000502:physiology; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology; D017063:Outcome Assessment, Health Care; D011930:Reaction Time / Q000502:physiology; D014888:Wechsler Scales
Cognitive proficiency index; General ability index; IQ; Late effects; Pediatric brain tumor