Background: Transfer of skills learned within the clinic environment to patients' home or community is important in post-inpatient brain injury rehabilitation (PBIR). Outcome measures used in PBIR assess level of independence during functional tasks; however, available functional instruments do not quantitate the environment in which the behaviors occur.
Objective: To examine the reliability and validity of an instrument used to assess patients' functional abilities while quantifying the amount of structure and distractions in the environment.
Methods: 2501 patients who sustained a traumatic brain injury (TBI) or cerebrovascular accident (CVA) and participated in a multidisciplinary PBIR program between 2006 and 2014 were identified retrospectively for this study. The PERPOS and MPAI-4 were used to assess functional abilities at admission and at discharge. Construct validity was assessed using a bivariate Spearman rho analysis A subsample of 56 consecutive admissions during 2014 were examined to determine inter-rater reliability. Intra-class correlation coefficient (ICC) and Kappa coefficients assessed inter-rater agreement of the total PERPOS and PERPOS subscales respectively.
Results: The PERPOS and MPAI-4 demonstrated a strong negative association among both TBI and CVA patients. Kappa scores for the three PERPOS scales each demonstrated good to excellent inter-rater agreement. The ICC for overall PERPOS scores fell in the good agreement range.
Conclusion: The PERPOS can be used reliably in PBIR to quantify patients' functional abilities within the context of environmental demands.
Keywords: Brain Injury; CVA; TBI; environment; outcome measure; rehabilitation.