Functional capacity evaluation as a performance measure: Evidence for a new approach for clients with chronic back pain

Objectives:
To report the research and development of a new approach to Functional Capacity Evaluation, the Gibson Approach to Functional Capacity Evaluation (GAPP FCE) for chronic back pain clients.

Methods:
Four studies, including pilot and feasibility testing, expert review, and preliminary interrater reliability examination, are described here. Participants included 7 healthy young adults and 19 rehabilitation clients with back pain who underwent assessment using the GAPP FCE. Thirteen therapists were trained in the approach and were silently observed administering the Functional Capacity Evaluations by at least 1 other trained therapists or the first investigator or both. An expert review using 5 expert occupational therapists was also conducted.

Results:
Study 1, the pilot with healthy individuals, indicated that the GAPP FCE was a feasible approach with good utility. Study 2, a pilot using 2 trained therapists assessing 5 back pain clients, supported the clinical feasibility of the approach. The expert review in Study 3 found support for GAPP FCE. Study 4, a trial of the approach with 14 rehabilitation clients, found support for the interrater reliability of recommendations for return to work based on performance in the GAPP FCE.

Discussion:
The evidence thus far available supports the GAPP FCE as an approach that provides a sound method for evaluating the performance of the physical demands of work with clients with chronic back pain. The tool has been shown to have good face and content validity, to meet acceptable test standards, and to have reasonable interrater reliability. Further research is occurring to look at a larger interrater reliability study, to further examine content validity, and to examine predictive validity.