Abstract
Background. As they guide people in performing a task, procedures are the heart of most manuals. It is, therefore, somewhat surprising that the theoretical and empirical knowledge of their nature has remained somewhat elusive. This paper describes a theoretical framework for procedures, summarized as the four components model, which is grounded in systems theory and rhetoric. Aim. The study addresses two research questions: (1) What are procedures made of? and (2) Which design guidelines for procedures can be abstracted from theory and research? Results. The model distinguishes between: goals, prerequisite states, unwanted states (warnings and problem-solving information), and actions and reactions. For each component pertinent research findings are summarized and lead to the formulation of design guidelines. Occasionally these guidelines are compared with existing procedures from a sample of 104 manuals to see how well theory and practice agree. Conclusion. The model offers a manageable and expandable framework for creating user support that is based on scientific research. It can be used for a systematic analysis of procedures and for their (re)design.