@article {131,
	title = {Evaluation of a computer-adaptive test for the assessment of depression (D-CAT) in clinical application},
	journal = {International Journal for Methods in Psychiatric Research},
	volume = {18},
	number = {1},
	year = {2009},
	note = {Journal articleInternational journal of methods in psychiatric researchInt J Methods Psychiatr Res. 2009 Feb 4.},
	month = {Feb 4},
	pages = {233-236},
	edition = {2009/02/06},
	abstract = {In the past, a German Computerized Adaptive Test, based on Item Response Theory (IRT), was developed for purposes of assessing the construct depression [Computer-adaptive test for depression (D-CAT)]. This study aims at testing the feasibility and validity of the real computer-adaptive application.The D-CAT, supplied by a bank of 64 items, was administered on personal digital assistants (PDAs) to 423 consecutive patients suffering from psychosomatic and other medical conditions (78 with depression). Items were adaptively administered until a predetermined reliability (r >/= 0.90) was attained. For validation purposes, the Hospital Anxiety and Depression Scale (HADS), the Centre for Epidemiological Studies Depression (CES-D) scale, and the Beck Depression Inventory (BDI) were administered. Another sample of 114 patients was evaluated using standardized diagnostic interviews [Composite International Diagnostic Interview (CIDI)].The D-CAT was quickly completed (mean 74 seconds), well accepted by the patients and reliable after an average administration of only six items. In 95\% of the cases, 10 items or less were needed for a reliable score estimate. Correlations between the D-CAT and the HADS, CES-D, and BDI ranged between r = 0.68 and r = 0.77. The D-CAT distinguished between diagnostic groups as well as established questionnaires do.The D-CAT proved an efficient, well accepted and reliable tool. Discriminative power was comparable to other depression measures, whereby the CAT is shorter and more precise. Item usage raises questions of balancing the item selection for content in the future. Copyright (c) 2009 John Wiley \& Sons, Ltd.},
	isbn = {1049-8931 (Print)},
	author = {Fliege, H. and Becker, J. and Walter, O. B. and Rose, M. and Bjorner, J. B. and Klapp, B. F.}
}
@article {227,
	title = {An evaluation of patient-reported outcomes found computerized adaptive testing was efficient in assessing stress perception},
	journal = {Journal of Clinical Epidemiology},
	volume = {62},
	number = {3},
	year = {2009},
	note = {Kocalevent, Ruya-DanielaRose, MatthiasBecker, JanineWalter, Otto BFliege, HerbertBjorner, Jakob BKleiber, DieterKlapp, Burghard FEvaluation StudiesUnited StatesJournal of clinical epidemiologyJ Clin Epidemiol. 2009 Mar;62(3):278-87, 287.e1-3. Epub 2008 Jul 18.},
	pages = {278-287},
	edition = {2008/07/22},
	abstract = {OBJECTIVES: This study aimed to develop and evaluate a first computerized adaptive test (CAT) for the measurement of stress perception (Stress-CAT), in terms of the two dimensions: exposure to stress and stress reaction. STUDY DESIGN AND SETTING: Item response theory modeling was performed using a two-parameter model (Generalized Partial Credit Model). The evaluation of the Stress-CAT comprised a simulation study and real clinical application. A total of 1,092 psychosomatic patients (N1) were studied. Two hundred simulees (N2) were generated for a simulated response data set. Then the Stress-CAT was given to n=116 inpatients, (N3) together with established stress questionnaires as validity criteria. RESULTS: The final banks included n=38 stress exposure items and n=31 stress reaction items. In the first simulation study, CAT scores could be estimated with a high measurement precision (SE<0.32; rho>0.90) using 7.0+/-2.3 (M+/-SD) stress reaction items and 11.6+/-1.7 stress exposure items. The second simulation study reanalyzed real patients data (N1) and showed an average use of items of 5.6+/-2.1 for the dimension stress reaction and 10.0+/-4.9 for the dimension stress exposure. Convergent validity showed significantly high correlations. CONCLUSIONS: The Stress-CAT is short and precise, potentially lowering the response burden of patients in clinical decision making.},
	keywords = {*Diagnosis, Computer-Assisted, Adolescent, Adult, Aged, Aged, 80 and over, Confidence Intervals, Female, Humans, Male, Middle Aged, Perception, Quality of Health Care/*standards, Questionnaires, Reproducibility of Results, Sickness Impact Profile, Stress, Psychological/*diagnosis/psychology, Treatment Outcome},
	isbn = {1878-5921 (Electronic)0895-4356 (Linking)},
	author = {Kocalevent, R. D. and Rose, M. and Becker, J. and Walter, O. B. and Fliege, H. and Bjorner, J. B. and Kleiber, D. and Klapp, B. F.}
}
@article {20,
	title = {Functioning and validity of a computerized adaptive test to measure anxiety (A CAT)},
	journal = {Depression and Anxiety},
	volume = {25},
	number = {12},
	year = {2008},
	pages = {E182-E194},
	abstract = {Background: The aim of this study was to evaluate the Computerized Adaptive Test to measure anxiety (A-CAT), a patient-reported outcome questionnaire that uses computerized adaptive testing to measure anxiety. Methods: The A-CAT builds on an item bank of 50 items that has been built using conventional item analyses and item response theory analyses. The A-CAT was administered on Personal Digital Assistants to n=357 patients diagnosed and treated at the department of Psychosomatic Medicine and Psychotherapy, Charit{\'e} Berlin, Germany. For validation purposes, two subgroups of patients (n=110 and 125) answered the A-CAT along with established anxiety and depression questionnaires. Results: The A-CAT was fast to complete (on average in 2 min, 38 s) and a precise item response theory based CAT score (reliability>.9) could be estimated after 4{\textendash}41 items. On average, the CAT displayed 6 items (SD=4.2). Convergent validity of the A-CAT was supported by correlations to existing tools (Hospital Anxiety and Depression Scale-A, Beck Anxiety Inventory, Berliner Stimmungs-Fragebogen A/D, and State Trait Anxiety Inventory: r=.56{\textendash}.66); discriminant validity between diagnostic groups was higher for the A-CAT than for other anxiety measures. Conclusions: The German A-CAT is an efficient, reliable, and valid tool for assessing anxiety in patients suffering from anxiety disorders and other conditions with significant potential for initial assessment and long-term treatment monitoring. Future research directions are to explore content balancing of the item selection algorithm of the CAT, to norm the tool to a healthy sample, and to develop practical cutoff scores. Depression and Anxiety, 2008. {\textcopyright} 2008 Wiley-Liss, Inc.},
	isbn = {1520-6394},
	author = {Becker, J. and Fliege, H. and Kocalevent, R. D. and Bjorner, J. B. and Rose, M. and Walter, O. B. and Klapp, B. F.}
}
@article {782,
	title = {Development and evaluation of a computer adaptive test for {\textquotedblleft}Anxiety{\textquotedblright} (Anxiety-CAT)},
	journal = {Quality of Life Research},
	volume = {16},
	year = {2007},
	pages = {143-155},
	author = {Walter, O. B. and Becker, J. and Bjorner, J. B. and Fliege, H. and Klapp, B. F. and Rose, M.}
}
@article {546,
	title = {Development of a computer-adaptive test for depression (D-CAT)},
	journal = {Quality of Life Research},
	volume = {14},
	year = {2005},
	pages = {2277{\textendash}2291},
	author = {Fliege, H. and Becker, J. and Walter, O. B. and Bjorner, J. B. and Klapp, B. F. and Rose, M.}
}
@article {2084,
	title = {Validating the German computerized adaptive test for anxiety on healthy sample (A-CAT)},
	journal = {Quality of Life Research},
	volume = {13},
	year = {2004},
	pages = {1515},
	author = {Becker, J. and Walter, O. B. and Fliege, H. and Bjorner, J. B. and Kocalevent, R. D. and Schmid, G. and Klapp, B. F. and Rose, M.}
}
