Expert decision making in relation to unanticipated blood glucose levels.

How people (N = 22) with long-standing Type I diabetes make everyday self-care decisions, specifically in regard to unanticipated blood glucose levels (UBGLs) was investigated using grounded theory. Participants differentiated between decisions made in familiar and typical situations and those made in novel situations. Decisions made in familiar situations were straightforward, arising from a confident appraisal of the cause of the UBGL. The primary focus of decision making in response to an UBGL in familiar situations was the decision about the course of action. The focus in unfamiliar situations was the appraisal of the cause of the UBGL. It was characterized by the participants' lack of confidence and by a non-linear progression in which the individual retraced previous phases of the decision-making process or proceeded to tangential steps. Participants matched the features of previously encountered situations to construct a story that explained the events in order to generate some plausible hypotheses. A number of contextual and mediating variables were identified as influencing the decision-making process and the decisions they made. The findings of this research demonstrate that the decision maker's familiarity with the situation influences the nature of the decision-making processes that are used.