Adaptive Forms: an interaction technique for entering structured data

Many software applications solicit input from the user via a "forms" paradi gm that emulates their paper equivalent. It exploits the users' familiarity with these and is well suited for the input of simple attribute-value data (name, phone number, etc.). The paper-forms paradigm starts breaking down when there is user input that may or may not be applicable depending on pre vious user input. In paper-based forms, this manifests itself by sections m arked "fill out only if you entered yes in question 8a above", and simple e lectronic forms suffer from the same problem-much space is taken up for inp ut fields that are not applicable. One possible approach to making only rel evant sections appear is to hand-write program fragments to hide and show t hem. As an alternative, we have developed a form specification language bas ed on a context-free grammar that encodes data dependencies of the input, t ogether with an accompanying run-time interpreter that uses novel layout te chniques for collapsing already-entered input fields, for "blending" input fields possibly yet to come, and for showing only the applicable sections o f the form. (C) 1998 Elsevier Science B.V. All rights reserved.