Reliability and validity of Functional Capacity Evaluation methods: a systematic review with reference to Blankenship system, Ergos work simulator, Ergo-Kit and Isernhagen work system

Objectives: Functional Capacity Evaluation methods (FCE) claim to measure the functional physical ability of a person to perform work-related tasks. The purpose of the present study was to systematically review the literature on the reliability and validity of four FCEs: the Blankenship system (BS), the ERGOS work simulator (EWS), the Ergo-Kit (EK) and the Isernhagen work system (IWS). Methods: A systematic literature search was conducted in five databases (CINAHL, Medline, Embase, OSH-ROM and Picarta) using the following keywords and their synonyms: functional capacity evaluation, reliability and validity. The search strategy was performed for relevance in titles and abstracts, and the databases were limited to literature published between 1980 and April 2004. Two independent reviewers applied the inclusion criteria to select all relevant articles and evaluated the methodological quality of all included articles. Results: The search resulted in 77 potential relevant references but only 12 papers were identified for inclusion and assessed for their methodological quality. The interrater reliability and predictive validity of the IWS were evaluated as good while the procedure used in the intrarater reliability (test-retest) studies was not rigorous enough to allow any conclusion. The concurrent validity of the EWS and EK was not demonstrated while no study was found on their reliability. No study was found on the reliability and validity of the BS. Conclusions: More rigorous studies are needed to demonstrate the reliability and the validity of FCE methods, especially the BS, EWS and EK.