An apparatus and method for determining difference in leg height of a standing patient by making a first measurement while the patient stands on a first foot, making a second measurement while the patient stands on a second foot, and determining the vertical distance between the first measurement and the second measurement. One embodiment incorporates a scale with a sliding wide measurement plate to measure the top of the head. Another embodiment provides a wide height measurement plate to retrofit existing height scales, and a fabrication kit for making that plate. In another embodiment the patient wears an apron with reference markings which may be observed through a movable reference grid. The observation may be manual or optically with a camera or scanner.