Using computerized adaptive testing to reduce the burden of mental health assessment.
OBJECTIVE
This study investigated the combination of item response theory and computerized adaptive testing (CAT) for psychiatric measurement as a means of reducing the burden of research and clinical assessments.


METHODS
Data were from 800 participants in outpatient treatment for a mood or anxiety disorder; they completed 616 items of the 626-item Mood and Anxiety Spectrum Scales (MASS) at two times. The first administration was used to design and evaluate a CAT version of the MASS by using post hoc simulation. The second confirmed the functioning of CAT in live testing.


RESULTS
Tests of competing models based on item response theory supported the scale's bifactor structure, consisting of a primary dimension and four group factors (mood, panic-agoraphobia, obsessive-compulsive, and social phobia). Both simulated and live CAT showed a 95% average reduction (585 items) in items administered (24 and 30 items, respectively) compared with administration of the full MASS. The correlation between scores on the full MASS and the CAT version was .93. For the mood disorder subscale, differences in scores between two groups of depressed patients--one with bipolar disorder and one without--on the full scale and on the CAT showed effect sizes of .63 (p<.003) and 1.19 (p<.001) standard deviation units, respectively, indicating better discriminant validity for CAT.


CONCLUSIONS
Instead of using small fixed-length tests, clinicians can create item banks with a large item pool, and a small set of the items most relevant for a given individual can be administered with no loss of information, yielding a dramatic reduction in administration time and patient and clinician burden.
Gibbons
Robert D
RD
Center for Health Statistics, University of Illinois at Chicago, Psychiatric Institute 457, M/C 912, Chicago, IL 60680-6998, USA. rdgib@uic.edu
Weiss
David J
DJ
Kupfer
David J
DJ
Frank
Ellen
E
Fagiolini
Andrea
A
Grochocinski
Victoria J
VJ
Bhaumik
Dulal K
DK
Stover
Angela
A
Bock
R Darrell
RD
Immekus
Jason C
JC
D000293:Adolescent; D000328:Adult; D000368:Aged; D000379:Agoraphobia / Q000175:diagnosis; D001008:Anxiety Disorders / Q000175:diagnosis; D001714:Bipolar Disorder / Q000175:diagnosis; D003936:Diagnosis, Computer-Assisted; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis*; D008875:Middle Aged; D019964:Mood Disorders / Q000175:diagnosis; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis; D016584:Panic Disorder / Q000175:diagnosis; D010698:Phobic Disorders / Q000175:diagnosis; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D013997:Time Factors