Bérard Anick, Kurz Xavier, Zuccarelli François, Abenhaim Lucien
Albert Einstein College of Medicine, Department of Emergency Medicine and of Epidemiology, Bronx, NY 10461, USA.
Angiology. 2002 Jan-Feb;53(1):21-8. doi: 10.1177/000331970205300104.
The objective of this study was to validate the Leg-O-Meter measure against the clinical assessment of edema made by physicians using data from a 1-year follow-up study of unselected patients with chronic venous disease of the leg (CVDL). The Leg-O-Meter consists of a tape measure fixed to a stand attached to a small board on which the patient is in standing position. Its reliability has been shown to be above 97%. Data from the Venous Insufficiency Epidemiologic and Economic Study (VEINES) were used: 1,521 patients from France, Belgium, Italy, and Quebec (Canada) who spontaneously consulted a physician between 1994 and 1995 with a complaint resulting from venous problems of the legs were included. Baseline variables included leg circumference measurements using the Leg-O-Meter; physicians were also asked to diagnose edema and report it as present or absent on each leg. Clinical edema and leg circumferences were assessed again 3 to 6 months after the baseline visit and 12 months after baseline. The tape measure of the Leg-O-Meter was fixed at 13 cm from the floor. The first and last assessments were used to evaluate the variation in edema during the follow-up period. Clinical variation in edema status was assessed as follows: improved, if edema was diagnosed at baseline but not at the final visit; unchanged, if edema was diagnosed at both visits; and worsened, if there was no diagnosis of edema at baseline but a diagnosis of edema was made at the final visit. Variation in measured edema was classified as improved if there was a decrease in leg circumference of more than 1 cm between baseline and final evaluation; unchanged, if the difference in leg circumference was between plus or minus 1 cm between the 2 assessments; and worsened, if there was an increase in leg circumference greater than 1 cm between the 2 assessments. Data-driven cut-off points were also used: 1.3 cm and 1.5 cm. Sensitivity and specificity of the Leg-O-Meter using physician diagnosis as "gold standard" were calculated. In addition, receiver operating characteristics (ROC) curves were calculated by using the 3 different leg circumference cut-off points in order to determine the accuracy of the Leg-O-Meter to detect changes in edema. The overall accuracy of the Leg-O-Meter was 0.84 (standard error (se) = 0.06). Accuracy was greater when 1.5 cm was used as a cut-point. The Leg-O-Meter is an objective, reliable, and standardized instrument to assess patients over time. A change of 1.5 cm between 2 measurements gives a valid estimate of improvement or worsening of edema, when compared to physicians' diagnosis. The Leg-O-Meter is also sensitive to any changes in leg circumferences, which is an advantage over the clinical evaluation of edema.
本研究的目的是利用对未经挑选的腿部慢性静脉疾病（CVDL）患者进行的为期1年的随访研究数据，将Leg - O - Meter测量结果与医生对水肿的临床评估进行验证。Leg - O - Meter由一个固定在支架上的卷尺组成，支架连接到一块小板上，患者站立在小板上。其可靠性已被证明高于97%。使用了静脉功能不全流行病学和经济研究（VEINES）的数据：纳入了1994年至1995年间自发咨询医生且因腿部静脉问题前来就诊的来自法国、比利时、意大利和魁北克（加拿大）的1521名患者。基线变量包括使用Leg - O - Meter测量腿部周长；医生还被要求诊断水肿，并报告每条腿上水肿的有无。在基线访视后3至6个月以及基线后12个月再次评估临床水肿和腿部周长。Leg - O - Meter的卷尺固定在距离地面13厘米处。首次和末次评估用于评估随访期间水肿的变化。水肿状态的临床变化评估如下：改善，如果基线时诊断为水肿但末次访视时未诊断为水肿；不变，如果两次访视均诊断为水肿；恶化，如果基线时未诊断为水肿但末次访视时诊断为水肿。如果基线和最终评估之间腿部周长减少超过1厘米，则测量的水肿变化分类为改善；不变，如果两次评估之间腿部周长差异在正负1厘米之间；恶化，如果两次评估之间腿部周长增加大于1厘米。还使用了数据驱动的截断点：1.3厘米和1.5厘米。计算以医生诊断为“金标准”的Leg - O - Meter的敏感性和特异性。此外，通过使用3个不同的腿部周长截断点计算受试者工作特征（ROC）曲线，以确定Leg - O - Meter检测水肿变化的准确性。Leg - O - Meter的总体准确性为0.84（标准误差（se）= 0.06）。当使用1.5厘米作为截断点时，准确性更高。Leg - O - Meter是一种客观、可靠且标准化的仪器，可随时间评估患者。与医生诊断相比，两次测量之间1.5厘米的变化给出了水肿改善或恶化的有效估计。Leg - O - Meter对腿部周长的任何变化也很敏感，这是相对于水肿临床评估的一个优势。
