Accuracy of infant emesis volume assessment

Even though nurses assess volume output for blood, emesis, and stool using visual processing, assessment accuracy has not been studied nor has the application of information-processing theory to visual assessment been shown. The purpose of this investigation was to determine the application of information-processing theory to accuracy in visual assessment of emesis. Nursing students and practicing pediatric nurses (N=109) participated in this nonexperimental study in which 20 randomly selected volumes were presented as visual displays of formula on receiving blankets. Subjects were asked to determine the volume. Findings showed that few displays were assessed accurately (M=2.63), but that subjects who have been taught to use a mental frame of reference in assessment were significantly more accurate. Error increased with the display volume. Additional analysis showed that subject practice role, nature of clinical practice, and number of displays assessed for weight accounted for significant proportions of variance in relative error. These findings are consistent with information-processing theory and suggest that nurses who are doing visual assessment should learn a processing method that presents a mental frame of reference with which they compare the observed volume. Further, perceived weight of the object observed should be added to visual processing to increase accuracy.