Simpson G
Clin Chem. 1987 Jun;33(6):753-6.
Published data are analyzed in order to estimate the accuracy of breath-alcohol measurements for subjects during absorption of orally ingested ethanol. Simultaneous measurements of breath alcohol concentration (BrAC) and venous blood alcohol concentration (VBAC) show that actual VBAC can be overestimated by more than 100% for a significant amount of time after drinking stops. The maximum error found for four individual subjects is +230%, +190%, +60%, and +30%. The magnitude of these errors indicates that results from quantitative evidential breath alcohol analyzers are far less accurate for the absorptive state than they are during the postabsorptive state, but the specifications for accuracy and precision given by manufacturers of these instruments do not reflect this. The results also indicate that there is a significant likelihood that subjects will be in the absorptive state when tested under field conditions. I conclude that estimates of BAC based on BrAC measurements are not reliable in the absorptive state and that the uncertainty associated with such estimates should be accounted for, particularly when the results are used in connection with law enforcement.
为了评估口服摄入乙醇后受试者呼气酒精测量的准确性，对已发表的数据进行了分析。呼气酒精浓度（BrAC）和静脉血酒精浓度（VBAC）的同步测量表明，饮酒停止后的相当长一段时间内，实际VBAC可能被高估100%以上。在四名个体受试者中发现的最大误差分别为+230%、+190%、+60%和+30%。这些误差的大小表明，定量证据呼气酒精分析仪在吸收状态下的结果远不如在吸收后状态下准确，但这些仪器制造商给出的准确性和精密度规格并未反映这一点。结果还表明，在现场条件下进行测试时，受试者处于吸收状态的可能性很大。我得出结论，基于BrAC测量的BAC估计在吸收状态下不可靠，并且应考虑与此类估计相关的不确定性，特别是当结果用于执法时。
