Lalys Loïc, Ruquet Michel, Tardivo Delphine, Laibi Salim, Bartoli Christophe, Adalian Pascal, Panuel Michel, Leonetti Georges, Foti Bruno
CNRS UPR 2147, Dynamique de l'Evolution Humaine: Individus, Populations, Espèces. 44 rue de l'Amiral Mouchez, 75014 Paris, France.
J Forensic Sci. 2011 Jan;56(1):220-3. doi: 10.1111/j.1556-4029.2010.01533.x. Epub 2010 Aug 23.
The few available studies on fetal age estimation concern very small samples, and statistical analysis is sometimes inadequate. In this survey, we used germs of deciduous teeth to estimate fetal age. Forty-nine fetuses and 40 mandibles were scanned, and observations and measurements were made on DentaScan images. After checking their repeatability and reproducibility (analysis of variance), we defined thresholds using Fisher's linear discriminant analysis to calculate the probability that a fetus was over or below a predefined age threshold. The forensic threshold which is of particular interest in France is 22 weeks amenorrhea. Relationships between fetal age and deciduous germ measurements were then sought by multiple linear regression. The thresholds gave very good results: 91.84% of good probability for the threshold of 22 weeks amenorrhea with no chance of error. The most precise age evaluation obtained nevertheless gave a range of ±4.6 weeks amenorrhea, so greater accuracy is still needed.
目前关于胎儿年龄估计的研究样本量非常小，而且统计分析有时并不充分。在本次调查中，我们使用乳牙胚来估计胎儿年龄。对49例胎儿和40例下颌骨进行了扫描，并在牙科扫描图像上进行了观察和测量。在检查了其可重复性和再现性（方差分析）之后，我们使用费舍尔线性判别分析定义阈值，以计算胎儿超过或低于预定义年龄阈值的概率。在法国特别受关注的法医阈值是停经22周。然后通过多元线性回归寻找胎儿年龄与乳牙胚测量值之间的关系。这些阈值给出了非常好的结果：停经22周阈值的正确概率为91.84%，且无误差可能性。然而，所获得的最精确年龄评估仍有±4.6周停经的范围，因此仍需要更高的准确性。
