02073nas a2200217 4500008004500000245013400045210006900179300001200248490000700260520127300267653003401540653004201574653002501616653001901641100001401660700001301674700001801687700001401705700001501719856012101734 2006 Engldsh 00aSimulated computerized adaptive test for patients with shoulder impairments was efficient and produced valid measures of function0 aSimulated computerized adaptive test for patients with shoulder  a290-2980 v593 a

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. 

10acomputerized adaptive testing10aFlexilevel Scale of Shoulder Function10aItem Response Theory10aRehabilitation1 aHart, D L1 aCook, KF1 aMioduski, J E1 aTeal, C R1 aCrane, P K uhttp://mail.iacat.org/content/simulated-computerized-adaptive-test-patients-shoulder-impairments-was-efficient-and-002001nas a2200205 4500008004100000020004600041245007900087210006900166260004100235300001400276490000700290520127200297653003001569653002501599653003401624100001301658700001801671700001601689856009001705 2005 eng d a0017-9124 (Print); 1475-6773 (Electronic)00aDynamic assessment of health outcomes: Time to let the CAT out of the bag?0 aDynamic assessment of health outcomes Time to let the CAT out of bBlackwell Publishing: United Kingdom a1694-17110 v403 aBackground: The use of item response theory (IRT) to measure self-reported outcomes has burgeoned in recent years. Perhaps the most important application of IRT is computer-adaptive testing (CAT), a measurement approach in which the selection of items is tailored for each respondent. Objective. To provide an introduction to the use of CAT in the measurement of health outcomes, describe several IRT models that can be used as the basis of CAT, and discuss practical issues associated with the use of adaptive scaling in research settings. Principal Points: The development of a CAT requires several steps that are not required in the development of a traditional measure including identification of "starting" and "stopping" rules. CAT's most attractive advantage is its efficiency. Greater measurement precision can be achieved with fewer items. Disadvantages of CAT include the high cost and level of technical expertise required to develop a CAT. Conclusions: Researchers, clinicians, and patients benefit from the availability of psychometrically rigorous measures that are not burdensome. CAT outcome measures hold substantial promise in this regard, but their development is not without challenges. (PsycINFO Database Record (c) 2007 APA, all rights reserved)10acomputer adaptive testing10aItem Response Theory10aself reported health outcomes1 aCook, KF1 aO'Malley, K J1 aRoddey, T S uhttp://mail.iacat.org/content/dynamic-assessment-health-outcomes-time-let-cat-out-bag