Åsberg Arne, Løfblad Lena, Hov Gunhild Garmo, Mikkelsen Gustav
Department of Clinical Chemistry, St. Olav's Hospital, Trondheim, Norway.
Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.
Scand J Clin Lab Invest. 2023 Oct;83(6):394-396. doi: 10.1080/00365513.2023.2241363. Epub 2023 Jul 28.
When comparing two analytical results for the same analyte, the clinicians may benefit from knowing the reference change values (RCVs) of the analyte. For Fibrosis-4 Index (FIB-4), a noninvasive test used for assessing the risk of liver fibrosis, no RCVs have been published for non-cirrhotic individuals. Therefore, we estimated RCVs for adults, using retrospectively collected data from outpatients with AST, ALT, and thrombocytes within the respective reference intervals. FIB-4 was calculated as (age × AST)/(thrombocytes × ALT). From two FIB-4 values in each patient we calculated the RCVs parametrically and non-parametrically. For both methods, we estimated the limits of the central 90% of the distribution of the ratio between the second and the first measurement. We obtained data on 599 outpatients with two blood tests taken 3 - 972 (median 258) days apart. The RCVs were 0.72 - 1.40 and 0.72 - 1.43, respectively, using the parametric and non-parametric methods. The 5 and 95 percentiles were not statistically significantly associated with sex, age, level of analyte, or the time between the measurements. The within-subject biological variation of FIB-4 was estimated to be 13.9%. Conclusion: In 90% of the patients the ratio between the second and the first FIB-4 result was approximately 0.7 - 1.4.
在比较同一分析物的两个分析结果时，临床医生了解该分析物的参考变化值（RCV）可能会有所帮助。对于用于评估肝纤维化风险的非侵入性检测方法——纤维化-4指数（FIB-4），尚未公布非肝硬化个体的RCV。因此，我们使用回顾性收集的门诊患者数据来估计成年人的RCV，这些患者的谷草转氨酶（AST）、谷丙转氨酶（ALT）和血小板计数均在各自的参考区间内。FIB-4的计算公式为（年龄×AST）/（血小板计数×ALT）。我们对每位患者的两个FIB-4值进行参数化和非参数化计算，得出RCV。对于这两种方法，我们估计了第二次测量值与第一次测量值之比分布的中心90%的范围。我们获得了599名门诊患者的数据，他们接受了两次血液检测，间隔时间为3至972天（中位数为258天）。使用参数化和非参数化方法得出的RCV分别为0.72至1.40和0.72至1.43。第5和第95百分位数与性别、年龄、分析物水平或测量间隔时间无统计学显著相关性。FIB-4的个体内生物学变异估计为13.9%。结论：在90%的患者中，第二次FIB-4结果与第一次结果之比约为0.7至1.4。
