Julius Centre for Health Sciences and Primary Care, University Medical Centre Utrecht, Utrecht, The Netherlands.
PLoS One. 2013 Aug 5;8(8):e71204. doi: 10.1371/journal.pone.0071204. Print 2013.
To evaluate the reliability of semiquantitative Vertebral Fracture Assessment (VFA) on chest Computed Tomography (CT).
Four observers performed VFA twice upon sagittal reconstructions of 50 routine clinical chest CTs. Intra- and interobserver agreement (absolute agreement or 95% Limits of Agreement) and reliability (Cohen's kappa or intraclass correlation coefficient(ICC)) were calculated for the visual VFA measures (fracture present, worst fracture grade, cumulative fracture grade on patient level) and for percentage height loss of each fractured vertebra compared to the adjacent vertebrae.
Observers classified 24-38% patients as having at least one vertebral fracture, giving rise to kappa's of 0.73-0.84 (intraobserver) and 0.56-0.81 (interobserver). For worst fracture grade we found good intraobserver (76-88%) and interobserver (74-88%) agreement, and excellent reliability with square-weighted kappa's of 0.84-0.90 (intraobserver) and 0.84-0.94 (interobserver). For cumulative fracture grade the 95% Limits of Agreement were maximally ±1,99 (intraobserver) and ±2,69 (interobserver) and the reliability (ICC) varied from 0.84-0.94 (intraobserver) and 0.74-0.94 (interobserver). For percentage height-loss on a vertebral level the 95% Limits of Agreement were maximally ±11,75% (intraobserver) and ±12,53% (interobserver). The ICC was 0.59-0.90 (intraobserver) and 0.53-0-82 (interobserver). Further investigation is needed to evaluate the prognostic value of this approach.
In conclusion, these results demonstrate acceptable reproducibility of VFA on CT.
评估胸部 CT 上半定量椎体骨折评估（VFA）的可靠性。
4 名观察者在 50 例常规临床胸部 CT 的矢状位重建上进行了两次 VFA。计算了视觉 VFA 测量值（存在骨折、最严重骨折等级、患者水平的累积骨折等级）以及与相邻椎体相比每个骨折椎体的高度损失百分比的观察者内和观察者间一致性（绝对一致性或 95% 一致性界限）和可靠性（Cohen's kappa 或组内相关系数（ICC））。
观察者将 24-38%的患者归类为至少有一个椎体骨折，导致kappa 值为 0.73-0.84（观察者内）和 0.56-0.81（观察者间）。对于最严重的骨折等级，我们发现观察者内（76-88%）和观察者间（74-88%）的一致性较好，并且具有极好的可靠性，平方加权 kappa 值为 0.84-0.90（观察者内）和 0.84-0.94（观察者间）。对于累积骨折等级，95%的一致性界限最大为±1.99（观察者内）和±2.69（观察者间），可靠性（ICC）从 0.84-0.94（观察者内）和 0.74-0.94（观察者间）不等。对于椎体水平的高度损失百分比，95%的一致性界限最大为±11.75%（观察者内）和±12.53%（观察者间）。ICC 值为 0.59-0.90（观察者内）和 0.53-0.82（观察者间）。需要进一步研究来评估这种方法的预后价值。
总之，这些结果表明 CT 上 VFA 的可重复性可以接受。
