TY - JOUR PY - 2015// TI - A multidimensional Rasch Analysis of the Functional Independence Measure based on the NIDILRR Traumatic Brain Injury Model Systems National Database JO - Journal of neurotrauma A1 - Pretz, Christopher R. A1 - Kean, Jacob A1 - Heinemann, Allen A1 - Kozlowski, Allan J. A1 - Bode, Rita A1 - Gebhardt, Eveline SP - 1358 EP - 1362 VL - 33 IS - 14 N2 - A number of studies have evaluated the psychometric properties of the FIMTM using Rasch analysis, though none have done so utilizing the NIDILRR Traumatic Brain Injury Model Systems National Database, a longitudinal database which captures demographic and outcome information on individuals with moderate to severe Traumatic Brain Injury across the United States. In the current study we examine the psychometric properties of the FIMTM as represented by persons within this database and demonstrate the FIMTM is comprised of three subscales representing cognitive, self-care, and mobility domains. These subscales were analyzed simultaneously utilizing a multivariate Rasch model in combination with a time dependent concurrent calibration scheme with the goal of creating a raw score-to-logit transformation which can be utilized to improve the accuracy of parametric statistical analyses. The bowel and bladder function items were removed due to misfit with the motor and cognitive items. Some motor items exhibited step disorder which was addressed by collapsing Categories 1-3 for Toileting, Stairs, Locomotion, Tub/Shower Transfers; Categories 1 and 2 for Toilet and Bed Transfers, and Categories 2 and 3 for Grooming. The strong correlations (r=0.82-0.96) among the three subscales suggest they should be modeled together. Coefficient alpha of 0.98 indicates high internal consistency. Keyform maps are provided to enhance clinical interpretation and application of study results.

Language: en

LA - en SN - 0897-7151 UR - http://dx.doi.org/10.1089/neu.2015.4138 ID - ref1 ER -