Heinen Eduarda Heydt, Lima Kelly Mônica Marinho E, Correia Raissa, Diefenthaeler Fernando, de Brito Fontana Heiliane
Biomechanics Laboratory, Federal University of Santa Catarina, Florianópolis, 88.040-900, Brazil.
Health Sciences Department, School of Science, Technology and Health, Federal University of Santa Catarina, Araranguá, 88.906-072, Brazil.
Foot (Edinb). 2021 Mar;46:101749. doi: 10.1016/j.foot.2020.101749. Epub 2020 Nov 17.
Given the increasing research interest in ultrasound plantar aponeurosis (PA) thickness measurements, this study aimed to analyze the inter and intra-rater reliability of independent sonograms and to identify the error related to the image analysis procedure.
Twenty-one healthy men participated in this study. Imaging of PA consisted of two independent sonograms per subject. Two raters (R1 and R2) evaluated each sonogram twice using standardized steps. Precision of the image analysis procedure was analyzed using the Bland and Altman plot and Intraclass Correlation Coefficient (ICC). Agreement estimates and ICC were used to assess absolute and relative inter and intra-rater reliability.
Reliability of PA thickness was found to depend strongly on the number of images acquired per subject. Intra-rater agreement for single measurements were 0.696 (R1) and 0.495 (R2), whereas average measurements yielded values of 0.821 (R1) and 0.662 (R2), respectively. Precision within a sonogram varied from ICC values of 0.873 to 0.960 (intra-rater) and 0.670 to 0.822 (inter-rater).
Most part of the error in PA thickness measurements seems to be related to the sonogram acquisition process and not to the visual inspection of the image. To minimize error, average values of a minimum of two images per subject should be used. The moderate agreement between raters found in this study ratifies the need of all measurements being made by the same rater or group of raters. If a single rater evaluates all subjects, performing multiple measurements over one image does not seem to affect ICC as much as acquiring multiple images.
鉴于对超声测量足底腱膜（PA）厚度的研究兴趣日益增加，本研究旨在分析独立超声图像在评估者间和评估者内的可靠性，并确定与图像分析程序相关的误差。
21名健康男性参与了本研究。PA成像包括为每位受试者采集两张独立的超声图像。两名评估者（R1和R2）使用标准化步骤对每张超声图像进行两次评估。使用Bland-Altman图和组内相关系数（ICC）分析图像分析程序的精度。一致性估计和ICC用于评估评估者间和评估者内的绝对和相对可靠性。
发现PA厚度的可靠性很大程度上取决于每位受试者采集的图像数量。单次测量的评估者内一致性，R1为0.696，R2为0.495，而平均测量值分别为0.821（R1）和0.662（R2）。超声图像内的精度，评估者内ICC值在0.873至0.960之间，评估者间ICC值在0.670至0.822之间。
PA厚度测量中的大部分误差似乎与超声图像采集过程有关，而非与图像的视觉检查有关。为了尽量减少误差，应使用每位受试者至少两张图像的平均值。本研究中评估者之间的中等一致性证实了所有测量应由同一评估者或一组评估者进行的必要性。如果由一名评估者评估所有受试者，对一张图像进行多次测量似乎对ICC的影响不如采集多张图像大。
