@article {84, title = {Letting the CAT out of the bag: Comparing computer adaptive tests and an 11-item short form of the Roland-Morris Disability Questionnaire}, journal = {Spine}, volume = {33}, number = {12}, year = {2008}, note = {Cook, Karon FChoi, Seung WCrane, Paul KDeyo, Richard AJohnson, Kurt LAmtmann, Dagmar5 P60-AR48093/AR/United States NIAMS5U01AR052171-03/AR/United States NIAMSComparative StudyResearch Support, N.I.H., ExtramuralUnited StatesSpineSpine. 2008 May 20;33(12):1378-83.}, month = {May 20}, pages = {1378-83}, edition = {2008/05/23}, abstract = {STUDY DESIGN: A post hoc simulation of a computer adaptive administration of the items of a modified version of the Roland-Morris Disability Questionnaire. OBJECTIVE: To evaluate the effectiveness of adaptive administration of back pain-related disability items compared with a fixed 11-item short form. SUMMARY OF BACKGROUND DATA: Short form versions of the Roland-Morris Disability Questionnaire have been developed. An alternative to paper-and-pencil short forms is to administer items adaptively so that items are presented based on a person{\textquoteright}s responses to previous items. Theoretically, this allows precise estimation of back pain disability with administration of only a few items. MATERIALS AND METHODS: Data were gathered from 2 previously conducted studies of persons with back pain. An item response theory model was used to calibrate scores based on all items, items of a paper-and-pencil short form, and several computer adaptive tests (CATs). RESULTS: Correlations between each CAT condition and scores based on a 23-item version of the Roland-Morris Disability Questionnaire ranged from 0.93 to 0.98. Compared with an 11-item short form, an 11-item CAT produced scores that were significantly more highly correlated with scores based on the 23-item scale. CATs with even fewer items also produced scores that were highly correlated with scores based on all items. For example, scores from a 5-item CAT had a correlation of 0.93 with full scale scores. Seven- and 9-item CATs correlated at 0.95 and 0.97, respectively. A CAT with a standard-error-based stopping rule produced scores that correlated at 0.95 with full scale scores. CONCLUSION: A CAT-based back pain-related disability measure may be a valuable tool for use in clinical and research contexts. Use of CAT for other common measures in back pain research, such as other functional scales or measures of psychological distress, may offer similar advantages.}, keywords = {*Disability Evaluation, *Health Status Indicators, Adult, Aged, Aged, 80 and over, Back Pain/*diagnosis/psychology, Calibration, Computer Simulation, Diagnosis, Computer-Assisted/*standards, Humans, Middle Aged, Models, Psychological, Predictive Value of Tests, Questionnaires/*standards, Reproducibility of Results}, isbn = {1528-1159 (Electronic)}, author = {Cook, K. F. and Choi, S. W. and Crane, P. K. and Deyo, R. A. and Johnson, K. L. and Amtmann, D.} } @article {86, title = {IRT health outcomes data analysis project: an overview and summary}, journal = {Quality of Life Research}, volume = {16}, number = {Suppl. 1}, year = {2007}, note = {Cook, Karon FTeal, Cayla RBjorner, Jakob BCella, DavidChang, Chih-HungCrane, Paul KGibbons, Laura EHays, Ron DMcHorney, Colleen AOcepek-Welikson, KatjaRaczek, Anastasia ETeresi, Jeanne AReeve, Bryce B1U01AR52171-01/AR/United States NIAMSR01 (CA60068)/CA/United States NCIY1-PC-3028-01/PC/United States NCIResearch Support, N.I.H., ExtramuralNetherlandsQuality of life research : an international journal of quality of life aspects of treatment, care and rehabilitationQual Life Res. 2007;16 Suppl 1:121-32. Epub 2007 Mar 10.}, pages = {121-132}, edition = {2007/03/14}, abstract = {BACKGROUND: In June 2004, the National Cancer Institute and the Drug Information Association co-sponsored the conference, "Improving the Measurement of Health Outcomes through the Applications of Item Response Theory (IRT) Modeling: Exploration of Item Banks and Computer-Adaptive Assessment." A component of the conference was presentation of a psychometric and content analysis of a secondary dataset. OBJECTIVES: A thorough psychometric and content analysis was conducted of two primary domains within a cancer health-related quality of life (HRQOL) dataset. RESEARCH DESIGN: HRQOL scales were evaluated using factor analysis for categorical data, IRT modeling, and differential item functioning analyses. In addition, computerized adaptive administration of HRQOL item banks was simulated, and various IRT models were applied and compared. SUBJECTS: The original data were collected as part of the NCI-funded Quality of Life Evaluation in Oncology (Q-Score) Project. A total of 1,714 patients with cancer or HIV/AIDS were recruited from 5 clinical sites. MEASURES: Items from 4 HRQOL instruments were evaluated: Cancer Rehabilitation Evaluation System-Short Form, European Organization for Research and Treatment of Cancer Quality of Life Questionnaire, Functional Assessment of Cancer Therapy and Medical Outcomes Study Short-Form Health Survey. RESULTS AND CONCLUSIONS: Four lessons learned from the project are discussed: the importance of good developmental item banks, the ambiguity of model fit results, the limits of our knowledge regarding the practical implications of model misfit, and the importance in the measurement of HRQOL of construct definition. With respect to these lessons, areas for future research are suggested. The feasibility of developing item banks for broad definitions of health is discussed.}, keywords = {*Data Interpretation, Statistical, *Health Status, *Quality of Life, *Questionnaires, *Software, Female, HIV Infections/psychology, Humans, Male, Neoplasms/psychology, Outcome Assessment (Health Care)/*methods, Psychometrics, Stress, Psychological}, isbn = {0962-9343 (Print)}, author = {Cook, K. F. and Teal, C. R. and Bjorner, J. B. and Cella, D. and Chang, C-H. and Crane, P. K. and Gibbons, L. E. and Hays, R. D. and McHorney, C. A. and Ocepek-Welikson, K. and Raczek, A. E. and Teresi, J. A. and Reeve, B. B.} } @article {328, title = {Psychometric evaluation and calibration of health-related quality of life item banks: plans for the Patient-Reported Outcomes Measurement Information System (PROMIS)}, journal = {Medical Care}, volume = {45}, number = {5 Suppl 1}, year = {2007}, note = {Reeve, Bryce BHays, Ron DBjorner, Jakob BCook, Karon FCrane, Paul KTeresi, Jeanne AThissen, DavidRevicki, Dennis AWeiss, David JHambleton, Ronald KLiu, HonghuGershon, RichardReise, Steven PLai, Jin-sheiCella, DavidPROMIS Cooperative GroupAG015815/AG/United States NIAResearch Support, N.I.H., ExtramuralUnited StatesMedical careMed Care. 2007 May;45(5 Suppl 1):S22-31.}, month = {May}, pages = {S22-31}, edition = {2007/04/20}, abstract = {BACKGROUND: The construction and evaluation of item banks to measure unidimensional constructs of health-related quality of life (HRQOL) is a fundamental objective of the Patient-Reported Outcomes Measurement Information System (PROMIS) project. OBJECTIVES: Item banks will be used as the foundation for developing short-form instruments and enabling computerized adaptive testing. The PROMIS Steering Committee selected 5 HRQOL domains for initial focus: physical functioning, fatigue, pain, emotional distress, and social role participation. This report provides an overview of the methods used in the PROMIS item analyses and proposed calibration of item banks. ANALYSES: Analyses include evaluation of data quality (eg, logic and range checking, spread of response distribution within an item), descriptive statistics (eg, frequencies, means), item response theory model assumptions (unidimensionality, local independence, monotonicity), model fit, differential item functioning, and item calibration for banking. RECOMMENDATIONS: Summarized are key analytic issues; recommendations are provided for future evaluations of item banks in HRQOL assessment.}, keywords = {*Health Status, *Information Systems, *Quality of Life, *Self Disclosure, Adolescent, Adult, Aged, Calibration, Databases as Topic, Evaluation Studies as Topic, Female, Humans, Male, Middle Aged, Outcome Assessment (Health Care)/*methods, Psychometrics, Questionnaires/standards, United States}, isbn = {0025-7079 (Print)}, author = {Reeve, B. B. and Hays, R. D. and Bjorner, J. B. and Cook, K. F. and Crane, P. K. and Teresi, J. A. and Thissen, D. and Revicki, D. A. and Weiss, D. J. and Hambleton, R. K. and Liu, H. and Gershon, R. C. and Reise, S. P. and Lai, J. S. and Cella, D.} } @article {237, title = {Factor analysis techniques for assessing sufficient unidimensionality of cancer related fatigue}, journal = {Quality of Life Research}, volume = {15}, number = {7}, year = {2006}, note = {0962-9343 (Print)Journal ArticleResearch Support, N.I.H., Extramural}, month = {Sep}, pages = {1179-90}, abstract = {BACKGROUND: Fatigue is the most common unrelieved symptom experienced by people with cancer. The purpose of this study was to examine whether cancer-related fatigue (CRF) can be summarized using a single score, that is, whether CRF is sufficiently unidimensional for measurement approaches that require or assume unidimensionality. We evaluated this question using factor analysis techniques including the theory-driven bi-factor model. METHODS: Five hundred and fifty five cancer patients from the Chicago metropolitan area completed a 72-item fatigue item bank, covering a range of fatigue-related concerns including intensity, frequency and interference with physical, mental, and social activities. Dimensionality was assessed using exploratory and confirmatory factor analysis (CFA) techniques. RESULTS: Exploratory factor analysis (EFA) techniques identified from 1 to 17 factors. The bi-factor model suggested that CRF was sufficiently unidimensional. CONCLUSIONS: CRF can be considered sufficiently unidimensional for applications that require unidimensionality. One such application, item response theory (IRT), will facilitate the development of short-form and computer-adaptive testing. This may further enable practical and accurate clinical assessment of CRF.}, keywords = {*Factor Analysis, Statistical, *Quality of Life, Aged, Chicago, Fatigue/*etiology, Female, Humans, Male, Middle Aged, Neoplasms/*complications, Questionnaires}, author = {Lai, J-S. and Crane, P. K. and Cella, D.} } @article {2074, title = {Simulated computerized adaptive test for patients with shoulder impairments was efficient and produced valid measures of function}, journal = {Journal of Clinical Epidemiology}, volume = {59}, year = {2006}, pages = {290-298}, abstract = {

Background and Objective: To test unidimensionality and local independence of a set of shoulder functional status (SFS) items,
develop a computerized adaptive test (CAT) of the items using a rating scale item response theory model (RSM), and compare discriminant validity of measures generated using all items (qIRT) and measures generated using the simulated CAT (qCAT).
Study Design and Setting: We performed a secondary analysis of data collected prospectively during rehabilitation of 400 patients
with shoulder impairments who completed 60 SFS items.
Results: Factor analytic techniques supported that the 42 SFS items formed a unidimensional scale and were locally independent. Except for five items, which were deleted, the RSM fit the data well. The remaining 37 SFS items were used to generate the CAT. On average, 6 items on were needed to estimate precise measures of function using the SFS CAT, compared with all 37 SFS items. The qIRT and qCAT measures were highly correlated (r 5 .96) and resulted in similar classifications of patients.
Conclusion: The simulated SFS CAT was efficient and produced precise, clinically relevant measures of functional status with good
discriminating ability.\ 

}, keywords = {computerized adaptive testing, Flexilevel Scale of Shoulder Function, Item Response Theory, Rehabilitation}, author = {Hart, D. L. and Cook, K. F. and Mioduski, J. E. and Teal, C. R. and Crane, P. K.} } @article {184, title = {Simulated computerized adaptive test for patients with shoulder impairments was efficient and produced valid measures of function}, journal = {Journal of Clinical Epidemiology}, volume = {59}, number = {3}, year = {2006}, note = {0895-4356 (Print)Journal ArticleValidation Studies}, pages = {290-8}, abstract = {BACKGROUND AND OBJECTIVE: To test unidimensionality and local independence of a set of shoulder functional status (SFS) items, develop a computerized adaptive test (CAT) of the items using a rating scale item response theory model (RSM), and compare discriminant validity of measures generated using all items (theta(IRT)) and measures generated using the simulated CAT (theta(CAT)). STUDY DESIGN AND SETTING: We performed a secondary analysis of data collected prospectively during rehabilitation of 400 patients with shoulder impairments who completed 60 SFS items. RESULTS: Factor analytic techniques supported that the 42 SFS items formed a unidimensional scale and were locally independent. Except for five items, which were deleted, the RSM fit the data well. The remaining 37 SFS items were used to generate the CAT. On average, 6 items were needed to estimate precise measures of function using the SFS CAT, compared with all 37 SFS items. The theta(IRT) and theta(CAT) measures were highly correlated (r = .96) and resulted in similar classifications of patients. CONCLUSION: The simulated SFS CAT was efficient and produced precise, clinically relevant measures of functional status with good discriminating ability.}, keywords = {*Computer Simulation, *Range of Motion, Articular, Activities of Daily Living, Adult, Aged, Aged, 80 and over, Factor Analysis, Statistical, Female, Humans, Male, Middle Aged, Prospective Studies, Reproducibility of Results, Research Support, N.I.H., Extramural, Research Support, U.S. Gov{\textquoteright}t, Non-P.H.S., Shoulder Dislocation/*physiopathology/psychology/rehabilitation, Shoulder Pain/*physiopathology/psychology/rehabilitation, Shoulder/*physiopathology, Sickness Impact Profile, Treatment Outcome}, author = {Hart, D. L. and Cook, K. F. and Mioduski, J. E. and Teal, C. R. and Crane, P. K.} } @article {238, title = {Item banking to improve, shorten and computerized self-reported fatigue: an illustration of steps to create a core item bank from the FACIT-Fatigue Scale}, journal = {Quality of Life Research}, volume = {12}, number = {5}, year = {2003}, note = {0962-9343Journal Article}, month = {Aug}, pages = {485-501}, abstract = {Fatigue is a common symptom among cancer patients and the general population. Due to its subjective nature, fatigue has been difficult to effectively and efficiently assess. Modern computerized adaptive testing (CAT) can enable precise assessment of fatigue using a small number of items from a fatigue item bank. CAT enables brief assessment by selecting questions from an item bank that provide the maximum amount of information given a person{\textquoteright}s previous responses. This article illustrates steps to prepare such an item bank, using 13 items from the Functional Assessment of Chronic Illness Therapy Fatigue Subscale (FACIT-F) as the basis. Samples included 1022 cancer patients and 1010 people from the general population. An Item Response Theory (IRT)-based rating scale model, a polytomous extension of the Rasch dichotomous model was utilized. Nine items demonstrating acceptable psychometric properties were selected and positioned on the fatigue continuum. The fatigue levels measured by these nine items along with their response categories covered 66.8\% of the general population and 82.6\% of the cancer patients. Although the operational CAT algorithms to handle polytomously scored items are still in progress, we illustrated how CAT may work by using nine core items to measure level of fatigue. Using this illustration, a fatigue measure comparable to its full-length 13-item scale administration was obtained using four items. The resulting item bank can serve as a core to which will be added a psychometrically sound and operational item bank covering the entire fatigue continuum.}, keywords = {*Health Status Indicators, *Questionnaires, Adult, Fatigue/*diagnosis/etiology, Female, Humans, Male, Middle Aged, Neoplasms/complications, Psychometrics, Research Support, Non-U.S. Gov{\textquoteright}t, Research Support, U.S. Gov{\textquoteright}t, P.H.S., Sickness Impact Profile}, author = {Lai, J-S. and Crane, P. K. and Cella, D. and Chang, C-H. and Bode, R. K. and Heinemann, A. W.} }