Development of an item bank for the assessment of depression in persons with mental illnesses and physical diseases using Rasch analysis.
OBJECTIVE
The calibration of item banks provides the basis for computerized adaptive testing that ensures high diagnostic precision and minimizes participants' test burden. The present study aimed at developing a new item bank that allows for assessing depression in persons with mental and persons with somatic diseases.


METHODS
The sample consisted of 161 participants treated for a depressive syndrome, and 206 participants with somatic illnesses (103 cardiologic, 103 otorhinolaryngologic; overall mean age = 44.1 years, SD =14.0; 44.7% women) to allow for validation of the item bank in both groups. Persons answered a pool of 182 depression items on a 5-point Likert scale.


RESULTS
Evaluation of Rasch model fit (infit < 1.3), differential item functioning, dimensionality, local independence, item spread, item and person separation (>2.0), and reliability (>.80) resulted in a bank of 79 items with good psychometric properties.


CONCLUSIONS
The bank provides items with a wide range of content coverage and may serve as a sound basis for computerized adaptive testing applications. It might also be useful for researchers who wish to develop new fixed-length scales for the assessment of depression in specific rehabilitation settings.
Forkmann
Thomas
T
Institute of Medical Psychology and Medical Sociology.
Boecker
Maren
M
Institute of Medical Psychology and Medical Sociology.
Norra
Christine
C
Department of Psychiatry and Psychotherapy LWL-University-Clinic, Ruhr-University Bochum.
Eberle
Nicole
N
Institute of Medical Psychology and Medical Sociology.
Kircher
Tilo
T
0000-0002-2514-2625
Department of Psychiatry and Psychotherapy, Phillips-University Marburg.
Schauerte
Patrick
P
Clinic for Cardiology, University Hospital of RWTH Aachen.
Mischke
Karl
K
Clinic for Cardiology, University Hospital of RWTH Aachen.
Westhofen
Martin
M
Clinic for Otorhinolaryngology, University Hospital of RWTH Aachen.
Gauggel
Siegfried
S
0000-0002-2742-4917
Institute of Medical Psychology and Medical Sociology.
Wirtz
Markus
M
University of Education.
D000223:Adaptation, Psychological; D000328:Adult; D000368:Aged; D003866:Depressive Disorder / Q000175:diagnosis* / Q000523:psychology; D003936:Diagnosis, Computer-Assisted; D005260:Female; D006331:Heart Diseases / Q000523:psychology*; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000523:psychology*; D008875:Middle Aged; D015233:Models, Statistical; D010038:Otorhinolaryngologic Diseases / Q000523:psychology*; D010552:Personality Assessment / Q000706:statistics & numerical data; D010555:Personality Inventory / Q000706:statistics & numerical data*; D011594:Psychometrics / Q000706:statistics & numerical data; D015203:Reproducibility of Results; D012803:Sick Role; D011795:Surveys and Questionnaires