The Multi-Directional Reach Test was devised by Dr. Roberta Newton at the Department of Physical Therapy at Temple University. Dr. Newton describes the test in her paper titled Validity of the Multi-Directional Reach Test: A Practical Measure for Limits of Stability in Older Adults as an "inexpensive screening tool to measure limits of stability in four directions." This ingenious tool is merely a 100 cm. ruler attached to a tripod. The vertical position of the ruler is adjusted to the subject's shoulder height. The tool is positioned in one of three ways--in front of the subject to measure both forward and reverse reach, and to the left and right of the subject to measure left and right reach, respectively. The subject is then asked to raise their arm for an initial reading. Once this reading is made, they stretch as far as possible along the ruler without allowing any part of their feet to come off of the ground. The subject's maximum reach is the difference between the initial reach and the stretch reach.
