@article {170,
	title = {Measuring global physical health in children with cerebral palsy: Illustration of a multidimensional bi-factor model and computerized adaptive testing},
	journal = {Quality of Life Research},
	volume = {18},
	number = {3},
	year = {2009},
	note = {Haley, Stephen MNi, PengshengDumas, Helene MFragala-Pinkham, Maria AHambleton, Ronald KMontpetit, KathleenBilodeau, NathalieGorton, George EWatson, KyleTucker, Carole AK02 HD045354-01A1/HD/NICHD NIH HHS/United StatesK02 HD45354-01A1/HD/NICHD NIH HHS/United StatesResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov{\textquoteright}tNetherlandsQuality of life research : an international journal of quality of life aspects of treatment, care and rehabilitationQual Life Res. 2009 Apr;18(3):359-70. Epub 2009 Feb 17.},
	month = {Apr},
	pages = {359-370},
	edition = {2009/02/18},
	abstract = {PURPOSE: The purposes of this study were to apply a bi-factor model for the determination of test dimensionality and a multidimensional CAT using computer simulations of real data for the assessment of a new global physical health measure for children with cerebral palsy (CP). METHODS: Parent respondents of 306 children with cerebral palsy were recruited from four pediatric rehabilitation hospitals and outpatient clinics. We compared confirmatory factor analysis results across four models: (1) one-factor unidimensional; (2) two-factor multidimensional (MIRT); (3) bi-factor MIRT with fixed slopes; and (4) bi-factor MIRT with varied slopes. We tested whether the general and content (fatigue and pain) person score estimates could discriminate across severity and types of CP, and whether score estimates from a simulated CAT were similar to estimates based on the total item bank, and whether they correlated as expected with external measures. RESULTS: Confirmatory factor analysis suggested separate pain and fatigue sub-factors; all 37 items were retained in the analyses. From the bi-factor MIRT model with fixed slopes, the full item bank scores discriminated across levels of severity and types of CP, and compared favorably to external instruments. CAT scores based on 10- and 15-item versions accurately captured the global physical health scores. CONCLUSIONS: The bi-factor MIRT CAT application, especially the 10- and 15-item versions, yielded accurate global physical health scores that discriminated across known severity groups and types of CP, and correlated as expected with concurrent measures. The CATs have potential for collecting complex data on the physical health of children with CP in an efficient manner.},
	keywords = {*Computer Simulation, *Health Status, *Models, Statistical, Adaptation, Psychological, Adolescent, Cerebral Palsy/*physiopathology, Child, Child, Preschool, Factor Analysis, Statistical, Female, Humans, Male, Massachusetts, Pennsylvania, Questionnaires, Young Adult},
	isbn = {0962-9343 (Print)0962-9343 (Linking)},
	author = {Haley, S. M. and Ni, P. and Dumas, H. M. and Fragala-Pinkham, M. A. and Hambleton, R. K. and Montpetit, K. and Bilodeau, N. and Gorton, G. E. and Watson, K. and Tucker, C. A.}
}
@article {169,
	title = {Computerized adaptive testing for follow-up after discharge from inpatient rehabilitation: II. Participation outcomes},
	journal = {Archives of Physical Medicine and Rehabilitation},
	volume = {89},
	number = {2},
	year = {2008},
	note = {Haley, Stephen MGandek, BarbaraSiebens, HilaryBlack-Schaffer, Randie MSinclair, Samuel JTao, WeiCoster, Wendy JNi, PengshengJette, Alan MK02 HD045354-01A1/HD/NICHD NIH HHS/United StatesK02 HD45354-01/HD/NICHD NIH HHS/United StatesR01 HD043568/HD/NICHD NIH HHS/United StatesR01 HD043568-01/HD/NICHD NIH HHS/United StatesResearch Support, N.I.H., ExtramuralUnited StatesArchives of physical medicine and rehabilitationArch Phys Med Rehabil. 2008 Feb;89(2):275-83.},
	month = {Feb},
	pages = {275-283},
	edition = {2008/01/30},
	abstract = {OBJECTIVES: To measure participation outcomes with a computerized adaptive test (CAT) and compare CAT and traditional fixed-length surveys in terms of score agreement, respondent burden, discriminant validity, and responsiveness. DESIGN: Longitudinal, prospective cohort study of patients interviewed approximately 2 weeks after discharge from inpatient rehabilitation and 3 months later. SETTING: Follow-up interviews conducted in patient{\textquoteright}s home setting. PARTICIPANTS: Adults (N=94) with diagnoses of neurologic, orthopedic, or medically complex conditions. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Participation domains of mobility, domestic life, and community, social, \& civic life, measured using a CAT version of the Participation Measure for Postacute Care (PM-PAC-CAT) and a 53-item fixed-length survey (PM-PAC-53). RESULTS: The PM-PAC-CAT showed substantial agreement with PM-PAC-53 scores (intraclass correlation coefficient, model 3,1, .71-.81). On average, the PM-PAC-CAT was completed in 42\% of the time and with only 48\% of the items as compared with the PM-PAC-53. Both formats discriminated across functional severity groups. The PM-PAC-CAT had modest reductions in sensitivity and responsiveness to patient-reported change over a 3-month interval as compared with the PM-PAC-53. CONCLUSIONS: Although continued evaluation is warranted, accurate estimates of participation status and responsiveness to change for group-level analyses can be obtained from CAT administrations, with a sizeable reduction in respondent burden.},
	keywords = {*Activities of Daily Living, *Adaptation, Physiological, *Computer Systems, *Questionnaires, Adult, Aged, Aged, 80 and over, Chi-Square Distribution, Factor Analysis, Statistical, Female, Humans, Longitudinal Studies, Male, Middle Aged, Outcome Assessment (Health Care)/*methods, Patient Discharge, Prospective Studies, Rehabilitation/*standards, Subacute Care/*standards},
	isbn = {1532-821X (Electronic)0003-9993 (Linking)},
	author = {Haley, S. M. and Gandek, B. and Siebens, H. and Black-Schaffer, R. M. and Sinclair, S. J. and Tao, W. and Coster, W. J. and Ni, P. and Jette, A. M.}
}
@article {5,
	title = {Efficiency and sensitivity of multidimensional computerized adaptive testing of pediatric physical functioning},
	journal = {Disability \& Rehabilitation},
	volume = {30},
	number = {6},
	year = {2008},
	note = {Allen, Diane DNi, PengshengHaley, Stephen MK02 HD45354-01/HD/NICHD NIH HHS/United StatesNIDDR H133P0001/DD/NCBDD CDC HHS/United StatesResearch Support, N.I.H., ExtramuralEnglandDisability and rehabilitationDisabil Rehabil. 2008;30(6):479-84.},
	pages = {479-84},
	edition = {2008/02/26},
	abstract = {PURPOSE: Computerized adaptive tests (CATs) have efficiency advantages over fixed-length tests of physical functioning but may lose sensitivity when administering extremely low numbers of items. Multidimensional CATs may efficiently improve sensitivity by capitalizing on correlations between functional domains. Using a series of empirical simulations, we assessed the efficiency and sensitivity of multidimensional CATs compared to a longer fixed-length test. METHOD: Parent responses to the Pediatric Evaluation of Disability Inventory before and after intervention for 239 children at a pediatric rehabilitation hospital provided the data for this retrospective study. Reliability, effect size, and standardized response mean were compared between full-length self-care and mobility subscales and simulated multidimensional CATs with stopping rules at 40, 30, 20, and 10 items. RESULTS: Reliability was lowest in the 10-item CAT condition for the self-care (r = 0.85) and mobility (r = 0.79) subscales; all other conditions had high reliabilities (r > 0.94). All multidimensional CAT conditions had equivalent levels of sensitivity compared to the full set condition for both domains. CONCLUSIONS: Multidimensional CATs efficiently retain the sensitivity of longer fixed-length measures even with 5 items per dimension (10-item CAT condition). Measuring physical functioning with multidimensional CATs could enhance sensitivity following intervention while minimizing response burden.},
	keywords = {*Disability Evaluation, Child, Computers, Disabled Children/*classification/rehabilitation, Efficiency, Humans, Outcome Assessment (Health Care), Psychometrics, Reproducibility of Results, Retrospective Studies, Self Care, Sensitivity and Specificity},
	isbn = {0963-8288 (Print)0963-8288 (Linking)},
	author = {Allen, D. D. and Ni, P. and Haley, S. M.}
}
@article {287,
	title = {Measuring physical functioning in children with spinal impairments with computerized adaptive testing},
	journal = {Journal of Pediatric Orthopedics},
	volume = {28},
	number = {3},
	year = {2008},
	note = {Mulcahey, M JHaley, Stephen MDuffy, TheresaPengsheng, NiBetz, Randal RK02 HD045354-01A1/HD/NICHD NIH HHS/United StatesUnited StatesJournal of pediatric orthopedicsJ Pediatr Orthop. 2008 Apr-May;28(3):330-5.},
	month = {Apr-May},
	pages = {330-5},
	edition = {2008/03/26},
	abstract = {BACKGROUND: The purpose of this study was to assess the utility of measuring current physical functioning status of children with scoliosis and kyphosis by applying computerized adaptive testing (CAT) methods. Computerized adaptive testing uses a computer interface to administer the most optimal items based on previous responses, reducing the number of items needed to obtain a scoring estimate. METHODS: This was a prospective study of 77 subjects (0.6-19.8 years) who were seen by a spine surgeon during a routine clinic visit for progress spine deformity. Using a multidimensional version of the Pediatric Evaluation of Disability Inventory CAT program (PEDI-MCAT), we evaluated content range, accuracy and efficiency, known-group validity, concurrent validity with the Pediatric Outcomes Data Collection Instrument, and test-retest reliability in a subsample (n = 16) within a 2-week interval. RESULTS: We found the PEDI-MCAT to have sufficient item coverage in both self-care and mobility content for this sample, although most patients tended to score at the higher ends of both scales. Both the accuracy of PEDI-MCAT scores as compared with a fixed format of the PEDI (r = 0.98 for both mobility and self-care) and test-retest reliability were very high [self-care: intraclass correlation (3,1) = 0.98, mobility: intraclass correlation (3,1) = 0.99]. The PEDI-MCAT took an average of 2.9 minutes for the parents to complete. The PEDI-MCAT detected expected differences between patient groups, and scores on the PEDI-MCAT correlated in expected directions with scores from the Pediatric Outcomes Data Collection Instrument domains. CONCLUSIONS: Use of the PEDI-MCAT to assess the physical functioning status, as perceived by parents of children with complex spinal impairments, seems to be feasible and achieves accurate and efficient estimates of self-care and mobility function. Additional item development will be needed at the higher functioning end of the scale to avoid ceiling effects for older children. LEVEL OF EVIDENCE: This is a level II prospective study designed to establish the utility of computer adaptive testing as an evaluation method in a busy pediatric spine practice.},
	keywords = {*Disability Evaluation, Adolescent, Child, Child, Preschool, Computer Simulation, Cross-Sectional Studies, Disabled Children/*rehabilitation, Female, Humans, Infant, Kyphosis/*diagnosis/rehabilitation, Male, Prospective Studies, Reproducibility of Results, Scoliosis/*diagnosis/rehabilitation},
	isbn = {0271-6798 (Print)0271-6798 (Linking)},
	author = {Mulcahey, M. J. and Haley, S. M. and Duffy, T. and Pengsheng, N. and Betz, R. R.}
}
@article {176,
	title = {Computerized adaptive testing for follow-up after discharge from inpatient rehabilitation: I. Activity outcomes},
	journal = {Archives of Physical Medicine and Rehabilitation},
	volume = {87},
	number = {8},
	year = {2006},
	note = {Haley, Stephen MSiebens, HilaryCoster, Wendy JTao, WeiBlack-Schaffer, Randie MGandek, BarbaraSinclair, Samuel JNi, PengshengK0245354-01/phsR01 hd043568/hd/nichdResearch Support, N.I.H., ExtramuralUnited StatesArchives of physical medicine and rehabilitationArch Phys Med Rehabil. 2006 Aug;87(8):1033-42.},
	month = {Aug},
	pages = {1033-42},
	edition = {2006/08/01},
	abstract = {OBJECTIVE: To examine score agreement, precision, validity, efficiency, and responsiveness of a computerized adaptive testing (CAT) version of the Activity Measure for Post-Acute Care (AM-PAC-CAT) in a prospective, 3-month follow-up sample of inpatient rehabilitation patients recently discharged home. DESIGN: Longitudinal, prospective 1-group cohort study of patients followed approximately 2 weeks after hospital discharge and then 3 months after the initial home visit. SETTING: Follow-up visits conducted in patients{\textquoteright} home setting. PARTICIPANTS: Ninety-four adults who were recently discharged from inpatient rehabilitation, with diagnoses of neurologic, orthopedic, and medically complex conditions. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Summary scores from AM-PAC-CAT, including 3 activity domains of movement and physical, personal care and instrumental, and applied cognition were compared with scores from a traditional fixed-length version of the AM-PAC with 66 items (AM-PAC-66). RESULTS: AM-PAC-CAT scores were in good agreement (intraclass correlation coefficient model 3,1 range, .77-.86) with scores from the AM-PAC-66. On average, the CAT programs required 43\% of the time and 33\% of the items compared with the AM-PAC-66. Both formats discriminated across functional severity groups. The standardized response mean (SRM) was greater for the movement and physical fixed form than the CAT; the effect size and SRM of the 2 other AM-PAC domains showed similar sensitivity between CAT and fixed formats. Using patients{\textquoteright} own report as an anchor-based measure of change, the CAT and fixed length formats were comparable in responsiveness to patient-reported change over a 3-month interval. CONCLUSIONS: Accurate estimates for functional activity group-level changes can be obtained from CAT administrations, with a considerable reduction in administration time.},
	keywords = {*Activities of Daily Living, *Adaptation, Physiological, *Computer Systems, *Questionnaires, Adult, Aged, Aged, 80 and over, Chi-Square Distribution, Factor Analysis, Statistical, Female, Humans, Longitudinal Studies, Male, Middle Aged, Outcome Assessment (Health Care)/*methods, Patient Discharge, Prospective Studies, Rehabilitation/*standards, Subacute Care/*standards},
	isbn = {0003-9993 (Print)},
	author = {Haley, S. M. and Siebens, H. and Coster, W. J. and Tao, W. and Black-Schaffer, R. M. and Gandek, B. and Sinclair, S. J. and Ni, P.}
}
@article {174,
	title = {Measurement precision and efficiency of multidimensional computer adaptive testing of physical functioning using the pediatric evaluation of disability inventory},
	journal = {Archives of Physical Medicine and Rehabilitation},
	volume = {87},
	number = {9},
	year = {2006},
	note = {Haley, Stephen MNi, PengshengLudlow, Larry HFragala-Pinkham, Maria AK02 hd45354-01/hd/nichdResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov{\textquoteright}tUnited StatesArchives of physical medicine and rehabilitationArch Phys Med Rehabil. 2006 Sep;87(9):1223-9.},
	month = {Sep},
	pages = {1223-9},
	edition = {2006/08/29},
	abstract = {OBJECTIVE: To compare the measurement efficiency and precision of a multidimensional computer adaptive testing (M-CAT) application to a unidimensional CAT (U-CAT) comparison using item bank data from 2 of the functional skills scales of the Pediatric Evaluation of Disability Inventory (PEDI). DESIGN: Using existing PEDI mobility and self-care item banks, we compared the stability of item calibrations and model fit between unidimensional and multidimensional Rasch models and compared the efficiency and precision of the U-CAT- and M-CAT-simulated assessments to a random draw of items. SETTING: Pediatric rehabilitation hospital and clinics. PARTICIPANTS: Clinical and normative samples. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Not applicable. RESULTS: The M-CAT had greater levels of precision and efficiency than the separate mobility and self-care U-CAT versions when using a similar number of items for each PEDI subdomain. Equivalent estimation of mobility and self-care scores can be achieved with a 25\% to 40\% item reduction with the M-CAT compared with the U-CAT. CONCLUSIONS: M-CAT applications appear to have both precision and efficiency advantages compared with separate U-CAT assessments when content subdomains have a high correlation. Practitioners may also realize interpretive advantages of reporting test score information for each subdomain when separate clinical inferences are desired.},
	keywords = {*Disability Evaluation, *Pediatrics, Adolescent, Child, Child, Preschool, Computers, Disabled Persons/*classification/rehabilitation, Efficiency, Humans, Infant, Outcome Assessment (Health Care), Psychometrics, Self Care},
	isbn = {0003-9993 (Print)},
	author = {Haley, S. M. and Ni, P. and Ludlow, L. H. and Fragala-Pinkham, M. A.}
}
@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 {167,
	title = {Score comparability of short forms and computerized adaptive testing: Simulation study with the activity measure for post-acute care},
	journal = {Archives of Physical Medicine and Rehabilitation},
	volume = {85},
	number = {4},
	year = {2004},
	note = {Haley, Stephen MCoster, Wendy JAndres, Patricia LKosinski, MarkNi, PengshengR01 hd43568/hd/nichdComparative StudyMulticenter StudyResearch Support, U.S. Gov{\textquoteright}t, Non-P.H.S.Research Support, U.S. Gov{\textquoteright}t, P.H.S.United StatesArchives of physical medicine and rehabilitationArch Phys Med Rehabil. 2004 Apr;85(4):661-6.},
	month = {Apr},
	pages = {661-6},
	edition = {2004/04/15},
	abstract = {OBJECTIVE: To compare simulated short-form and computerized adaptive testing (CAT) scores to scores obtained from complete item sets for each of the 3 domains of the Activity Measure for Post-Acute Care (AM-PAC). DESIGN: Prospective study. SETTING: Six postacute health care networks in the greater Boston metropolitan area, including inpatient acute rehabilitation, transitional care units, home care, and outpatient services. PARTICIPANTS: A convenience sample of 485 adult volunteers who were receiving skilled rehabilitation services. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Inpatient and community-based short forms and CAT applications were developed for each of 3 activity domains (physical \& mobility, personal care \& instrumental, applied cognition) using item pools constructed from new items and items from existing postacute care instruments. RESULTS: Simulated CAT scores correlated highly with score estimates from the total item pool in each domain (4- and 6-item CAT r range,.90-.95; 10-item CAT r range,.96-.98). Scores on the 10-item short forms constructed for inpatient and community settings also provided good estimates of the AM-PAC item pool scores for the physical \& movement and personal care \& instrumental domains, but were less consistent in the applied cognition domain. Confidence intervals around individual scores were greater in the short forms than for the CATs. CONCLUSIONS: Accurate scoring estimates for AM-PAC domains can be obtained with either the setting-specific short forms or the CATs. The strong relationship between CAT and item pool scores can be attributed to the CAT{\textquoteright}s ability to select specific items to match individual responses. The CAT may have additional advantages over short forms in practicality, efficiency, and the potential for providing more precise scoring estimates for individuals.},
	keywords = {Boston, Factor Analysis, Statistical, Humans, Outcome Assessment (Health Care)/*methods, Prospective Studies, Questionnaires/standards, Rehabilitation/*standards, Subacute Care/*standards},
	isbn = {0003-9993 (Print)},
	author = {Haley, S. M. and Coster, W. J. and Andres, P. L. and Kosinski, M. and Ni, P.}
}
