Timing of the breath analyzer: does it make a difference?

The purpose of this article is to examine in an emergency room (ER) population the concordance of self-reports of no alcohol consumption prior to injury with breath-analyzer readings in two groups: (1) those patients from whom reports were obtained after they were breath analyzed compared to (2) patients from whom reports were obtained prior to obtaining the breath-analyzer reading. Data were collected on a probability sample of patients attending three health maintenance organization ERs. Among those sampled were 159 patients admitted for initial treatment of an injury, who were breath analyzed within 6 hours of the event and reported no drinking following the event that lead to injury. Of these, 119 were breath analyzed prior to the interview, and none who reported not drinking were positive on the breath analyzer, while of the 37 breath analyzed after the interview, only one was positive who had reported not drinking. Obtaining the breath-analyzer reading following the interview was not found to affect the rate of refusal to provide a breath-analyzer reading; however, it was found to adversely affect obtaining the breath-analyzer reading for other reasons. The data suggest that the concordance of negative self-reports of consumption with breath-analyzer readings remains high in ER populations regardless of when the breath-analyzer reading is obtained; however, it appears best to obtain the reading prior to interviewing the patient for reasons explained below.