1. Measuring activity limitations in climbing stairs: development of a hierarchical scale for patients with lower-extremity disorders living at home1 
Leo D Roorda, MD, PT, Marij E Roebroeck, PhD, Theo van Tilburg, PhD, Gustaaf J Lankhorst, MD, PhD, Lex M Bouter, PhD 
Archives of Physical Medicine and Rehabilitation 
Volume 85, Issue 6, Pages (June 2004)
DOI: /j.apmr

2. Fig 1
Mean item scores for amputees and nonamputees. Mean item scores for amputees are on the x axis and for nonamputees, on the y axis. Low mean item scores designate the items indicating severe limitations, and high mean item scores designate the items indicating minor limitations. The numbers near the data points refer to the item numbers. For a full explanation of the items, see appendix 1. An identity line is drawn through the origin with a slope of 1. Items with major and significant deviations from the identity line demonstrate DIF. ∗Items with DIF.
Archives of Physical Medicine and Rehabilitation  , DOI: ( /j.apmr )