%0 Journal Article %J Journal of Rheumatology %D 2009 %T Progress in assessing physical function in arthritis: PROMIS short forms and computerized adaptive testing %A Fries, J.F. %A Cella, D. %A Rose, M. %A Krishnan, E. %A Bruce, B. %K *Disability Evaluation %K *Outcome Assessment (Health Care) %K Arthritis/diagnosis/*physiopathology %K Health Surveys %K Humans %K Prognosis %K Reproducibility of Results %X OBJECTIVE: Assessing self-reported physical function/disability with the Health Assessment Questionnaire Disability Index (HAQ) and other instruments has become central in arthritis research. Item response theory (IRT) and computerized adaptive testing (CAT) techniques can increase reliability and statistical power. IRT-based instruments can improve measurement precision substantially over a wider range of disease severity. These modern methods were applied and the magnitude of improvement was estimated. METHODS: A 199-item physical function/disability item bank was developed by distilling 1865 items to 124, including Legacy Health Assessment Questionnaire (HAQ) and Physical Function-10 items, and improving precision through qualitative and quantitative evaluation in over 21,000 subjects, which included about 1500 patients with rheumatoid arthritis and osteoarthritis. Four new instruments, (A) Patient-Reported Outcomes Measurement Information (PROMIS) HAQ, which evolved from the original (Legacy) HAQ; (B) "best" PROMIS 10; (C) 20-item static (short) forms; and (D) simulated PROMIS CAT, which sequentially selected the most informative item, were compared with the HAQ. RESULTS: Online and mailed administration modes yielded similar item and domain scores. The HAQ and PROMIS HAQ 20-item scales yielded greater information content versus other scales in patients with more severe disease. The "best" PROMIS 20-item scale outperformed the other 20-item static forms over a broad range of 4 standard deviations. The 10-item simulated PROMIS CAT outperformed all other forms. CONCLUSION: Improved items and instruments yielded better information. The PROMIS HAQ is currently available and considered validated. The new PROMIS short forms, after validation, are likely to represent further improvement. CAT-based physical function/disability assessment offers superior performance over static forms of equal length. %B Journal of Rheumatology %7 2009/09/10 %V 36 %P 2061-2066 %8 Sep %@ 0315-162X (Print)0315-162X (Linking) %G eng %M 19738214 %0 Journal Article %J American Journal of Physical Medicine and Rehabilitation %D 2005 %T Measuring physical function in patients with complex medical and postsurgical conditions: a computer adaptive approach %A Siebens, H. %A Andres, P. L. %A Pengsheng, N. %A Coster, W. J. %A Haley, S. M. %K Activities of Daily Living/*classification %K Adult %K Aged %K Cohort Studies %K Continuity of Patient Care %K Disability Evaluation %K Female %K Health Services Research %K Humans %K Male %K Middle Aged %K Postoperative Care/*rehabilitation %K Prognosis %K Recovery of Function %K Rehabilitation Centers %K Rehabilitation/*standards %K Sensitivity and Specificity %K Sickness Impact Profile %K Treatment Outcome %X 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. %B American Journal of Physical Medicine and Rehabilitation %V 84 %P 741-8 %8 Oct %G eng %M 16205429