Reliability, validity and responsiveness of instruments to assess disabilities in personal care in patients with rheumatic disorders. A systematic review.

The first aim was to make an inventory of available instruments and questionnaires for the assessment of disabilities in personal care in patients with rheumatic disorders. The second aim was to investigate which of these instruments have acceptable, methodological quality with regard to reliability, validity and responsiveness. The third aim was to investigate the assumption that convergent validity results in stronger correlations when validated against a more similar construct.