@article {7,
	title = {Development and preliminary testing of a computerized adaptive assessment of chronic pain},
	journal = {Journal of Pain},
	volume = {10},
	number = {9},
	year = {2009},
	note = {Anatchkova, Milena DSaris-Baglama, Renee NKosinski, MarkBjorner, Jakob B1R43AR052251-01A1/AR/NIAMS NIH HHS/United StatesEvaluation StudiesResearch Support, N.I.H., ExtramuralUnited StatesThe journal of pain : official journal of the American Pain SocietyJ Pain. 2009 Sep;10(9):932-43.},
	month = {Sep},
	pages = {932-943},
	edition = {2009/07/15},
	abstract = {The aim of this article is to report the development and preliminary testing of a prototype computerized adaptive test of chronic pain (CHRONIC PAIN-CAT) conducted in 2 stages: (1) evaluation of various item selection and stopping rules through real data-simulated administrations of CHRONIC PAIN-CAT; (2) a feasibility study of the actual prototype CHRONIC PAIN-CAT assessment system conducted in a pilot sample. Item calibrations developed from a US general population sample (N = 782) were used to program a pain severity and impact item bank (kappa = 45), and real data simulations were conducted to determine a CAT stopping rule. The CHRONIC PAIN-CAT was programmed on a tablet PC using QualityMetric{\textquoteright}s Dynamic Health Assessment (DYHNA) software and administered to a clinical sample of pain sufferers (n = 100). The CAT was completed in significantly less time than the static (full item bank) assessment (P < .001). On average, 5.6 items were dynamically administered by CAT to achieve a precise score. Scores estimated from the 2 assessments were highly correlated (r = .89), and both assessments discriminated across pain severity levels (P < .001, RV = .95). Patients{\textquoteright} evaluations of the CHRONIC PAIN-CAT were favorable. PERSPECTIVE: This report demonstrates that the CHRONIC PAIN-CAT is feasible for administration in a clinic. The application has the potential to improve pain assessment and help clinicians manage chronic pain.},
	keywords = {*Computers, *Questionnaires, Activities of Daily Living, Adaptation, Psychological, Chronic Disease, Cohort Studies, Disability Evaluation, Female, Humans, Male, Middle Aged, Models, Psychological, Outcome Assessment (Health Care), Pain Measurement/*methods, Pain, Intractable/*diagnosis/psychology, Psychometrics, Quality of Life, User-Computer Interface},
	isbn = {1528-8447 (Electronic)1526-5900 (Linking)},
	author = {Anatchkova, M. D. and Saris-Baglama, R. N. and Kosinski, M. and Bjorner, J. B.}
}
@article {52,
	title = {Improving patient reported outcomes using item response theory and computerized adaptive testing},
	journal = {Journal of Rheumatology},
	volume = {34},
	number = {6},
	year = {2007},
	note = {Chakravarty, Eliza FBjorner, Jakob BFries, James FAr052158/ar/niamsConsensus Development ConferenceResearch Support, N.I.H., ExtramuralCanadaThe Journal of rheumatologyJ Rheumatol. 2007 Jun;34(6):1426-31.},
	month = {Jun},
	pages = {1426-31},
	edition = {2007/06/07},
	abstract = {OBJECTIVE: Patient reported outcomes (PRO) are considered central outcome measures for both clinical trials and observational studies in rheumatology. More sophisticated statistical models, including item response theory (IRT) and computerized adaptive testing (CAT), will enable critical evaluation and reconstruction of currently utilized PRO instruments to improve measurement precision while reducing item burden on the individual patient. METHODS: We developed a domain hierarchy encompassing the latent trait of physical function/disability from the more general to most specific. Items collected from 165 English-language instruments were evaluated by a structured process including trained raters, modified Delphi expert consensus, and then patient evaluation. Each item in the refined data bank will undergo extensive analysis using IRT to evaluate response functions and measurement precision. CAT will allow for real-time questionnaires of potentially smaller numbers of questions tailored directly to each individual{\textquoteright}s level of physical function. RESULTS: Physical function/disability domain comprises 4 subdomains: upper extremity, trunk, lower extremity, and complex activities. Expert and patient review led to consensus favoring use of present-tense "capability" questions using a 4- or 5-item Likert response construct over past-tense "performance"items. Floor and ceiling effects, attribution of disability, and standardization of response categories were also addressed. CONCLUSION: By applying statistical techniques of IRT through use of CAT, existing PRO instruments may be improved to reduce questionnaire burden on the individual patients while increasing measurement precision that may ultimately lead to reduced sample size requirements for costly clinical trials.},
	keywords = {*Rheumatic Diseases/physiopathology/psychology, Clinical Trials, Data Interpretation, Statistical, Disability Evaluation, Health Surveys, Humans, International Cooperation, Outcome Assessment (Health Care)/*methods, Patient Participation/*methods, Research Design/*trends, Software},
	isbn = {0315-162X (Print)},
	author = {Chakravarty, E. F. and Bjorner, J. B. and Fries, J.F.}
}
@article {357,
	title = {Measuring physical function in patients with complex medical and postsurgical conditions: a computer adaptive approach},
	journal = {American Journal of Physical Medicine and Rehabilitation},
	volume = {84},
	number = {10},
	year = {2005},
	note = {0894-9115 (Print)Comparative StudyJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, U.S. Gov{\textquoteright}t, P.H.S.},
	month = {Oct},
	pages = {741-8},
	abstract = {OBJECTIVE: To examine whether the range of disability in the medically complex and postsurgical populations receiving rehabilitation is adequately sampled by the new Activity Measure--Post-Acute Care (AM-PAC), and to assess whether computer adaptive testing (CAT) can derive valid patient scores using fewer questions. DESIGN: Observational study of 158 subjects (mean age 67.2 yrs) receiving skilled rehabilitation services in inpatient (acute rehabilitation hospitals, skilled nursing facility units) and community (home health services, outpatient departments) settings for recent-onset or worsening disability from medical (excluding neurological) and surgical (excluding orthopedic) conditions. Measures were interviewer-administered activity questions (all patients) and physical functioning portion of the SF-36 (outpatients) and standardized chart items (11 Functional Independence Measure (FIM), 19 Standardized Outcome and Assessment Information Set (OASIS) items, and 22 Minimum Data Set (MDS) items). Rasch modeling analyzed all data and the relationship between person ability estimates and average item difficulty. CAT assessed the ability to derive accurate patient scores using a sample of questions. RESULTS: The 163-item activity item pool covered the range of physical movement and personal and instrumental activities. CAT analysis showed comparable scores between estimates using 10 items or the total item pool. CONCLUSION: The AM-PAC can assess a broad range of function in patients with complex medical illness. CAT achieves valid patient scores using fewer questions.},
	keywords = {Activities of Daily Living/*classification, Adult, Aged, Cohort Studies, Continuity of Patient Care, Disability Evaluation, Female, Health Services Research, Humans, Male, Middle Aged, Postoperative Care/*rehabilitation, Prognosis, Recovery of Function, Rehabilitation Centers, Rehabilitation/*standards, Sensitivity and Specificity, Sickness Impact Profile, Treatment Outcome},
	author = {Siebens, H. and Andres, P. L. and Pengsheng, N. and Coster, W. J. and Haley, S. M.}
}
@article {168,
	title = {Activity outcome measurement for postacute care},
	journal = {Medical Care},
	volume = {42},
	number = {1 Suppl},
	year = {2004},
	note = {0025-7079Journal ArticleMulticenter Study},
	pages = {I49-161},
	abstract = {BACKGROUND: Efforts to evaluate the effectiveness of a broad range of postacute care services have been hindered by the lack of conceptually sound and comprehensive measures of outcomes. It is critical to determine a common underlying structure before employing current methods of item equating across outcome instruments for future item banking and computer-adaptive testing applications. OBJECTIVE: To investigate the factor structure, reliability, and scale properties of items underlying the Activity domains of the International Classification of Functioning, Disability and Health (ICF) for use in postacute care outcome measurement. METHODS: We developed a 41-item Activity Measure for Postacute Care (AM-PAC) that assessed an individual{\textquoteright}s execution of discrete daily tasks in his or her own environment across major content domains as defined by the ICF. We evaluated the reliability and discriminant validity of the prototype AM-PAC in 477 individuals in active rehabilitation programs across 4 rehabilitation settings using factor analyses, tests of item scaling, internal consistency reliability analyses, Rasch item response theory modeling, residual component analysis, and modified parallel analysis. RESULTS: Results from an initial exploratory factor analysis produced 3 distinct, interpretable factors that accounted for 72\% of the variance: Applied Cognition (44\%), Personal Care \& Instrumental Activities (19\%), and Physical \& Movement Activities (9\%); these 3 activity factors were verified by a confirmatory factor analysis. Scaling assumptions were met for each factor in the total sample and across diagnostic groups. Internal consistency reliability was high for the total sample (Cronbach alpha = 0.92 to 0.94), and for specific diagnostic groups (Cronbach alpha = 0.90 to 0.95). Rasch scaling, residual factor, differential item functioning, and modified parallel analyses supported the unidimensionality and goodness of fit of each unique activity domain. CONCLUSIONS: This 3-factor model of the AM-PAC can form the conceptual basis for common-item equating and computer-adaptive applications, leading to a comprehensive system of outcome instruments for postacute care settings.},
	keywords = {*Self Efficacy, *Sickness Impact Profile, Activities of Daily Living/*classification/psychology, Adult, Aftercare/*standards/statistics \& numerical data, Aged, Boston, Cognition/physiology, Disability Evaluation, Factor Analysis, Statistical, Female, Human, Male, Middle Aged, Movement/physiology, Outcome Assessment (Health Care)/*methods/statistics \& numerical data, Psychometrics, Questionnaires/standards, Rehabilitation/*standards/statistics \& numerical data, Reproducibility of Results, Sensitivity and Specificity, Support, U.S. Gov{\textquoteright}t, Non-P.H.S., Support, U.S. Gov{\textquoteright}t, P.H.S.},
	author = {Haley, S. M. and Coster, W. J. and Andres, P. L. and Ludlow, L. H. and Ni, P. and Bond, T. L. and Sinclair, S. J. and Jette, A. M.}
}
@article {87,
	title = {Refining the conceptual basis for rehabilitation outcome measurement: personal care and instrumental activities domain},
	journal = {Medical Care},
	volume = {42},
	number = {1 Suppl},
	year = {2004},
	note = {0025-7079Journal Article},
	month = {Jan},
	pages = {I62-172},
	abstract = {BACKGROUND: Rehabilitation outcome measures routinely include content on performance of daily activities; however, the conceptual basis for item selection is rarely specified. These instruments differ significantly in format, number, and specificity of daily activity items and in the measurement dimensions and type of scale used to specify levels of performance. We propose that a requirement for upper limb and hand skills underlies many activities of daily living (ADL) and instrumental activities of daily living (IADL) items in current instruments, and that items selected based on this definition can be placed along a single functional continuum. OBJECTIVE: To examine the dimensional structure and content coverage of a Personal Care and Instrumental Activities item set and to examine the comparability of items from existing instruments and a set of new items as measures of this domain. METHODS: Participants (N = 477) from 3 different disability groups and 4 settings representing the continuum of postacute rehabilitation care were administered the newly developed Activity Measure for Post-Acute Care (AM-PAC), the SF-8, and an additional setting-specific measure: FIM (in-patient rehabilitation); MDS (skilled nursing facility); MDS-PAC (postacute settings); OASIS (home care); or PF-10 (outpatient clinic). Rasch (partial-credit model) analyses were conducted on a set of 62 items covering the Personal Care and Instrumental domain to examine item fit, item functioning, and category difficulty estimates and unidimensionality. RESULTS: After removing 6 misfitting items, the remaining 56 items fit acceptably along the hypothesized continuum. Analyses yielded different difficulty estimates for the maximum score (eg, "Independent performance") for items with comparable content from different instruments. Items showed little differential item functioning across age, diagnosis, or severity groups, and 92\% of the participants fit the model. CONCLUSIONS: ADL and IADL items from existing rehabilitation outcomes instruments that depend on skilled upper limb and hand use can be located along a single continuum, along with the new personal care and instrumental items of the AM-PAC addressing gaps in content. Results support the validity of the proposed definition of the Personal Care and Instrumental Activities dimension of function as a guide for future development of rehabilitation outcome instruments, such as linked, setting-specific short forms and computerized adaptive testing approaches.},
	keywords = {*Self Efficacy, *Sickness Impact Profile, Activities of Daily Living/*classification/psychology, Adult, Aged, Aged, 80 and over, Disability Evaluation, Factor Analysis, Statistical, Female, Humans, Male, Middle Aged, Outcome Assessment (Health Care)/*methods/statistics \& numerical data, Questionnaires/*standards, Recovery of Function/physiology, Rehabilitation/*standards/statistics \& numerical data, Reproducibility of Results, Research Support, U.S. Gov{\textquoteright}t, Non-P.H.S., Research Support, U.S. Gov{\textquoteright}t, P.H.S., Sensitivity and Specificity},
	author = {Coster, W. J. and Haley, S. M. and Andres, P. L. and Ludlow, L. H. and Bond, T. L. and Ni, P. S.}
}
@article {30,
	title = {Calibration of an item pool for assessing the burden of headaches: an application of item response theory to the Headache Impact Test (HIT)},
	journal = {Quality of Life Research},
	volume = {12},
	number = {8},
	year = {2003},
	note = {0962-9343Journal Article},
	pages = {913-933},
	abstract = {BACKGROUND: Measurement of headache impact is important in clinical trials, case detection, and the clinical monitoring of patients. Computerized adaptive testing (CAT) of headache impact has potential advantages over traditional fixed-length tests in terms of precision, relevance, real-time quality control and flexibility. OBJECTIVE: To develop an item pool that can be used for a computerized adaptive test of headache impact. METHODS: We analyzed responses to four well-known tests of headache impact from a population-based sample of recent headache sufferers (n = 1016). We used confirmatory factor analysis for categorical data and analyses based on item response theory (IRT). RESULTS: In factor analyses, we found very high correlations between the factors hypothesized by the original test constructers, both within and between the original questionnaires. These results suggest that a single score of headache impact is sufficient. We established a pool of 47 items which fitted the generalized partial credit IRT model. By simulating a computerized adaptive health test we showed that an adaptive test of only five items had a very high concordance with the score based on all items and that different worst-case item selection scenarios did not lead to bias. CONCLUSION: We have established a headache impact item pool that can be used in CAT of headache impact.},
	keywords = {*Cost of Illness, *Decision Support Techniques, *Sickness Impact Profile, Adolescent, Adult, Aged, Comparative Study, Disability Evaluation, Factor Analysis, Statistical, Headache/*psychology, Health Surveys, Human, Longitudinal Studies, Middle Aged, Migraine/psychology, Models, Psychological, Psychometrics/*methods, Quality of Life/*psychology, Software, Support, Non-U.S. Gov{\textquoteright}t},
	author = {Bjorner, J. B. and Kosinski, M. and Ware, J. E., Jr.}
}
