Assessment and Evaluation of a Crosswalk between the Functional Independence Measure and the Continuity Assessment Record and Evaluation: a NIDILRR-funded TBI Model Systems Study.

Abstract

Objective: To evaluate crosswalks between the Continuity Assessment Record and Evaluation (CARE) measure and the Functional Independence Measure (FIM™) Motor subscale scores in a sample of persons with traumatic brain injury (TBI), given the CARE measure's development by the Centers for Medicare and Medicaid Services in 2005 to assess motor function in all post-acute rehabilitation settings and its intended continuity with previous measures DESIGN: Crosswalks were created using three methodologies (Expert Opinion, Equipercentile, Rasch). The dataset was split into training and validation datasets. Each crosswalk was evaluated using reduction in uncertainty, percent of each crosswalked score falling within ½ standard deviation (SD) of the reference measure, population invariance, comparison of statistical moments and effect size.

Setting: Record Abstraction PARTICIPANTS: 982 persons who were hospitalized and received inpatient rehabilitation after TBI and had both FIM and CARE collected at inpatient rehabilitation admission and discharge.

Interventions: NA MAIN OUTCOME MEASURES: Crosswalk between the FIM and CARE RESULTS: In the training dataset, the Expert Opinion crosswalk met all criteria except the direction of population invariance within the race category. The Equipercentile methodology satisfied all criteria. The Rasch model met all criteria except for a difference in directionality in the skewness of the distributions and 80% of scores not falling within ½ SD of the reference assessment. Results from the validation sample differed from the population invariance criteria, in which the age categories were in opposite directions and had observed differences between standardized mean difference for age that exceeded the threshold of 0.08 for both the Equipercentile and Rasch crosswalks.

Conclusion: All three crosswalk methods produced acceptable criteria for use, indicating that motor/physical functional outcome can be compared between cohorts assessed using CARE and FIM measures. Researchers can compare cohorts that have been assessed using these instruments using any of these crosswalks. However, we do not recommend using these crosswalks for longitudinal analyses.