Fleege J C, Baak J P, Smeulders A W
Pathological Institute, Free University Hospital, Amsterdam, The Netherlands.
Hum Pathol. 1988 May;19(5):513-7. doi: 10.1016/s0046-8177(88)80196-5.
The morphometric analysis of nuclear characteristics by means of a graphic tablet is, in principle, objective and highly reproducible. However, a recent study found considerable variation in the morphometric assessments, which was in contrast to the findings of others. The way in which measurements were performed differed in these studies. Therefore, measuring system factors that can potentially influence the quantitative results were analyzed systematically. One observer, experienced in microscopic analysis and working with a commercially available graphic tablet, conducted all the measurements, thus excluding interobserver variation. The tracing speed, localization (on the graphic tablet), magnification, pen and cursor usage, shape, and orientation on the graphic tablet were analyzed. A nomogram was developed for cursor application that indicates the relation between "projected" particle size, tracing speed, and required coefficient of variation (CV). When the influence of these factors is taken into account, a measuring system can be tuned optimally. With such a regimen, the CV can be kept below 1.5%. Our results show that in the assessment of morphometric features with the use of a graphic tablet, errors due to the measuring system can be virtually eliminated.
原则上，借助图形输入板对细胞核特征进行形态计量分析是客观且高度可重复的。然而，最近的一项研究发现形态计量评估存在相当大的差异，这与其他研究结果形成对比。这些研究中测量的方式有所不同。因此，对可能影响定量结果的测量系统因素进行了系统分析。由一位在显微镜分析方面经验丰富且使用市售图形输入板的观察者进行所有测量，从而排除观察者间差异。分析了追踪速度、在图形输入板上的定位、放大倍数、笔和光标的使用、形状以及在图形输入板上的方向。针对光标应用开发了一个列线图，该图表明了“投影”颗粒大小、追踪速度和所需变异系数（CV）之间的关系。当考虑这些因素的影响时，可以对测量系统进行最佳调整。采用这样的方案，变异系数可保持在1.5%以下。我们的结果表明，在使用图形输入板评估形态计量特征时，测量系统导致的误差几乎可以消除。
