McAra Sylvia, Trevethan Robert
J Am Podiatr Med Assoc. 2018 Mar;108(2):115-125. doi: 10.7547/16-036.
Insufficient information exists about the nature of toe-brachial indices (TBIs) and how best to obtain them, yet their validity may be particularly important for the identification and management of peripheral artery disease and cardiovascular disease risk. We explore ways in which valid TBI measurements might be obtained.
The TBI data were recorded from 97 people with subnormal toe pressures. Most people provided three TBI readings from each foot on six different occasions over a 6-month period. The foot with the lower baseline TBI was noted.
For most people, only small inconsistencies existed among the three readings taken from each foot on a single occasion, and there were no consistent differences based on sequence. However, for some people there were noticeable and unsystematic differences among the measures. Selecting any specific one of the three readings based on its sequential position, or averaging specific readings, did not yield TBIs that were unequivocally typical for a person, and taking the lowest reading of each set seemed to offer the most expedient solution in this context. That permitted baseline descriptive statistics to be produced for both the higher and lower pressure feet, between which there was a statistically significant TBI difference.
Accurate and consistent TBI readings cannot be assumed for people with subnormal toe pressures, and taking only a single reading or indiscriminately averaging readings seems inadvisable. Two readings and, if they are discrepant, additional readings, are recommended for each foot, ideally on several occasions, and careful consideration should be given to determine the most representative reading for each foot. Cuff sizes and other sources of inaccuracy or distortion should not be ignored, and standardized protocols for obtaining TBIs are recommended.
关于趾臂指数（TBI）的性质以及如何最佳获取该指数的信息不足，但其有效性对于外周动脉疾病和心血管疾病风险的识别与管理可能尤为重要。我们探索获取有效TBI测量值的方法。
记录了97名趾压低于正常水平者的TBI数据。大多数人在6个月内的6个不同时间点，从每只脚获取了3次TBI读数。记录下基线TBI较低的那只脚。
对于大多数人而言，在单次测量中从每只脚获取的3次读数之间仅存在微小的不一致，且基于测量顺序不存在一致的差异。然而，对于一些人来说，测量值之间存在明显且无规律的差异。根据测量顺序选择3次读数中的任何一个特定读数，或对特定读数求平均值，都无法得出明确代表个体特征的TBI值，在此情况下取每组中的最低读数似乎是最便捷的解决方案。这使得能够为较高压力脚和较低压力脚生成基线描述性统计数据，两者之间的TBI差异具有统计学意义。
对于趾压低于正常水平的人，不能假定能获得准确且一致的TBI读数，仅进行单次读数或不加区分地对读数求平均值似乎并不可取。建议每只脚进行两次读数，如果两者存在差异，则进行额外读数，理想情况下在多个时间点进行，并且应仔细考虑以确定每只脚最具代表性的读数。不应忽视袖带尺寸以及其他不准确或失真的来源，建议采用标准化方案获取TBI。
