Line of reasoning as a representation of nurses' clinical decision making.

Line of reasoning (LOR) is offered as an alternative representation of clinical decision making for studies using protocol analysis. A LOR is defined as an argument or set of arguments leading to a conclusion. Because LOR combines both knowledge and cognitive processes, it provides a more complete representation of how a person uses knowledge to make a decision in a particular situation than do other representations. Operationalization of LOR in the form of templates and narratives enhances systematic data interpretation and coding. The use of LOR as a representation is illustrated in a study of critical care nurses' clinical decision making, specifically the determination of a patient's readiness to wean from mechanical ventilation.