Abstract
The Oswestry Disability Index has been one of the most common disease specific measures for patients with back symptoms in the world, and has been cross-culturally translated into Japanese without loosing psychometric properties of the original versions. This instrument correlates well with mental sub-scales of the SF-36 as well as physical ones, and it is suited to situations in which patients have persistent severe disability, though it functions satisfactorily in groups with mild to moderate disability. New instruments have been developed with higher reliability and validity compared to older ones in Japan. The availability and its history of the Oswestry Disability Index in a wide range of languages have great advantages in direct comparison with past numerous studies through the same instrument.
